diff --git a/manifest b/manifest
index 3da48e9607..02548aebcc 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Made\scode\sto\sremove\sunused\sparameter\swarning\spart\sof\sthe\sconditional.\s\sTicket\s#3610.\s(CVS\s6219)
-D 2009-01-30T16:09:23
+C Fix\sa\sround-off\serror\swhen\smoving\sdates\sby\snegative\smodifier\samounts.\nTicket\s#3618.\s\sEnhance\sthe\s"NNN\syears"\smodifier\sto\saccept\sfractional\nyears.\s(CVS\s6220)
+D 2009-01-30T17:27:44
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in 3871d308188cefcb7c5ab20da4c7b6aad023bc52
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -109,7 +109,7 @@ F src/btreeInt.h 44bcbfe387ba99a3a9f2527bd12fa1bb8bc574b3
 F src/build.c c8bf5dcef4d5889bc57eecdb8b3dba178e5e06a8
 F src/callback.c bee8949d619b1b7b1e4dfac8a19c5116ae1dd12a
 F src/complete.c cb14e06dbe79dee031031f0d9e686ff306afe07c
-F src/date.c b4db68e6cd7f3c7b437c440fca5863692b8cd026
+F src/date.c 870770dde3fb56772ab247dfb6a6eda44d16cfbc
 F src/delete.c 6249005bdd8f85db6ec5f31ddb5c07de023693cc
 F src/expr.c 76dc3dc83b56ab8db50a772714fac49def8bbf12
 F src/fault.c dc88c821842157460750d2d61a8a8b4197d047ff
@@ -291,7 +291,7 @@ F test/crash8.test 5b32966fcb58fd616d24ce94303420351d076eb9
 F test/crashtest1.c 09c1c7d728ccf4feb9e481671e29dda5669bbcc2
 F test/createtab.test 199cf68f44e5d9e87a0b8afc7130fdeb4def3272
 F test/cse.test 277350a26264495e86b1785f34d2d0c8600e021c
-F test/date.test 4ea54e26feea7c24dfc7fad1b2b87da21ff12380
+F test/date.test bb2cc648333c04d09e8e23cfc0cddc398c334a92
 F test/default.test 252298e42a680146b1dd64f563b95bdf088d94fb
 F test/delete.test f171c1011395a8dd63169438fe1d8cc625eb7442
 F test/delete2.test 3a03f2cca1f9a67ec469915cb8babd6485db43fa
@@ -693,7 +693,7 @@ F tool/speedtest16.c c8a9c793df96db7e4933f0852abb7a03d48f2e81
 F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
-P 0a2c7f740397c5c6373434c75d73c2714f14dd32
-R 649046167725b542f7b218aebaf5f5d8
-U shane
-Z 487e1bd5693e1aade7bfd1bf63c7b518
+P c5dca1146de72071ed2e5fdf6890f41682272587
+R 6a74041552de27456797035382a955bb
+U drh
+Z 4f589fc1347644d84b8da190a4ca5065
diff --git a/manifest.uuid b/manifest.uuid
index e8922d3936..ea269c0d28 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-c5dca1146de72071ed2e5fdf6890f41682272587
\ No newline at end of file
+86be908c5e77ba2b9ac98e394fa987b443d790f8
\ No newline at end of file
diff --git a/src/date.c b/src/date.c
index 670efd2bd8..c8aeceffba 100644
--- a/src/date.c
+++ b/src/date.c
@@ -16,7 +16,7 @@
 ** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
 ** All other code has file scope.
 **
-** $Id: date.c,v 1.101 2009/01/28 02:55:29 drh Exp $
+** $Id: date.c,v 1.102 2009/01/30 17:27:44 drh Exp $
 **
 ** SQLite processes all times and dates as Julian Day numbers.  The
 ** dates and times are stored as the number of days since noon
@@ -629,6 +629,7 @@ static int parseModifier(const char *zMod, DateTime *p){
     case '7':
     case '8':
     case '9': {
+      double rRounder;
       n = getValue(z, &r);
       assert( n>=1 );
       if( z[n]==':' ){
@@ -661,14 +662,15 @@ static int parseModifier(const char *zMod, DateTime *p){
       if( z[n-1]=='s' ){ z[n-1] = 0; n--; }
       computeJD(p);
       rc = 0;
+      rRounder = r<0 ? -0.5 : +0.5;
       if( n==3 && strcmp(z,"day")==0 ){
-        p->iJD += (sqlite3_int64)(r*86400000.0 + 0.5);
+        p->iJD += (sqlite3_int64)(r*86400000.0 + rRounder);
       }else if( n==4 && strcmp(z,"hour")==0 ){
-        p->iJD += (sqlite3_int64)(r*(86400000.0/24.0) + 0.5);
+        p->iJD += (sqlite3_int64)(r*(86400000.0/24.0) + rRounder);
       }else if( n==6 && strcmp(z,"minute")==0 ){
-        p->iJD += (sqlite3_int64)(r*(86400000.0/(24.0*60.0)) + 0.5);
+        p->iJD += (sqlite3_int64)(r*(86400000.0/(24.0*60.0)) + rRounder);
       }else if( n==6 && strcmp(z,"second")==0 ){
-        p->iJD += (sqlite3_int64)(r*(86400000.0/(24.0*60.0*60.0)) + 0.5);
+        p->iJD += (sqlite3_int64)(r*(86400000.0/(24.0*60.0*60.0)) + rRounder);
       }else if( n==5 && strcmp(z,"month")==0 ){
         int x, y;
         computeYMD_HMS(p);
@@ -680,13 +682,17 @@ static int parseModifier(const char *zMod, DateTime *p){
         computeJD(p);
         y = (int)r;
         if( y!=r ){
-          p->iJD += (sqlite3_int64)((r - y)*30.0*86400000.0 + 0.5);
+          p->iJD += (sqlite3_int64)((r - y)*30.0*86400000.0 + rRounder);
         }
       }else if( n==4 && strcmp(z,"year")==0 ){
+        int y = (int)r;
         computeYMD_HMS(p);
-        p->Y += (int)r;
+        p->Y += y;
         p->validJD = 0;
         computeJD(p);
+        if( y!=r ){
+          p->iJD += (sqlite3_int64)((r - y)*365.0*86400000.0 + rRounder);
+        }
       }else{
         rc = 1;
       }
diff --git a/test/date.test b/test/date.test
index 466fb6516f..1e0b748078 100644
--- a/test/date.test
+++ b/test/date.test
@@ -11,7 +11,7 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this file is testing date and time functions.
 #
-# $Id: date.test,v 1.31 2008/07/08 02:12:37 drh Exp $
+# $Id: date.test,v 1.32 2009/01/30 17:27:44 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -454,6 +454,28 @@ datetest 13.6 {strftime('%Y-%m-%d %H:%M:%S', '2007-01-01 23:59:59.6')} \
 datetest 13.7 {strftime('%Y-%m-%d %H:%M:%f', '2007-01-01 23:59:59.6')} \
   {2007-01-01 23:59:59.600}
 
+# Ticket #3618
+datetest 13.11 {julianday(2454832.5,'-1 day')} {2454831.5}
+datetest 13.12 {julianday(2454832.5,'+1 day')} {2454833.5}
+datetest 13.13 {julianday(2454832.5,'-1.5 day')} {2454831.0}
+datetest 13.14 {julianday(2454832.5,'+1.5 day')} {2454834.0}
+datetest 13.15 {julianday(2454832.5,'-3 hours')} {2454832.375}
+datetest 13.16 {julianday(2454832.5,'+3 hours')} {2454832.625}
+datetest 13.17 {julianday(2454832.5,'-45 minutes')} {2454832.46875}
+datetest 13.18 {julianday(2454832.5,'+45 minutes')} {2454832.53125}
+datetest 13.19 {julianday(2454832.5,'-675 seconds')} {2454832.4921875}
+datetest 13.20 {julianday(2454832.5,'+675 seconds')} {2454832.5078125}
+datetest 13.21 {julianday(2454832.5,'-1.5 months')} {2454786.5}
+datetest 13.22 {julianday(2454832.5,'+1.5 months')} {2454878.5}
+datetest 13.23 {julianday(2454832.5,'-1.5 years')} {2454284.0}
+datetest 13.24 {julianday(2454832.5,'+1.5 years')} {2455380.0}
+
+datetest 13.30 {date('2000-01-01','+1.5 years')} {2001-07-02}
+datetest 13.31 {date('2001-01-01','+1.5 years')} {2002-07-02}
+datetest 13.32 {date('2002-01-01','+1.5 years')} {2003-07-02}
+datetest 13.33 {date('2002-01-01','-1.5 years')} {2000-07-02}
+datetest 13.34 {date('2001-01-01','-1.5 years')} {1999-07-02}
+
 # Test for issues reported by BareFeet (list.sql at tandb.com.au)
 # on mailing list on 2008-06-12.
 #