=== modified file Modules/_sre.c
--- Modules/_sre.c 2008-09-26 17:00:31 +0000
+++ Modules/_sre.c 2008-09-30 00:34:20 +0000
@@ -631,6 +631,7 @@
     backtrack_item = &context->backtrack_chunk->items[context->backtrack_chunk->count++];
     backtrack_item->op = op;
     backtrack_item->pattern_ptr = pattern_ptr;
+    backtrack_item->text_start = context->text_start;
     backtrack_item->text_ptr = context->text_ptr;
     backtrack_item->index = index;
     backtrack_item->repeat_counter = context->repeat_counter[index];
@@ -922,6 +923,7 @@
             result = SRE_SAVE_MARKS(&context);
             if (result != 0)
                 return SRE_CLEANUP(&context, state, result);
+            context.text_start = state->beginning;
             context.pattern_ptr++;
             break;
         case SRE_OP_ASSERT_NOT:
@@ -934,6 +936,7 @@
             result = SRE_SAVE_MARKS(&context);
             if (result != 0)
                 return SRE_CLEANUP(&context, state, result);
+            context.text_start = state->beginning;
             context.pattern_ptr++;
             break;
         case SRE_OP_ATOMIC:
@@ -1062,6 +1065,7 @@
             TRACE(("|%p|%p|END_ASSERT\n", context.pattern_ptr, context.text_ptr));
             SRE_DISCARD_UNTIL_OP(&context, SRE_OP_ASSERT);
             backtrack_item = &context.backtrack_chunk->items[context.backtrack_chunk->count - 1];
+            context.text_start = backtrack_item->text_start;
             context.text_ptr = backtrack_item->text_ptr;
             SRE_DISCARD_BACKTRACK(&context);
             SRE_RESTORE_MARKS(&context);
@@ -1071,8 +1075,11 @@
         {
             // Assert not subpattern.
             // <ASSERT_NOT> <skip to end> ... <END_ASSERT_NOT>
+            SRE_BACKTRACK_ITEM* backtrack_item;
             TRACE(("|%p|%p|END_ASSERT_NOT\n", context.pattern_ptr, context.text_ptr));
             SRE_DISCARD_UNTIL_OP(&context, SRE_OP_ASSERT_NOT);
+            backtrack_item = &context.backtrack_chunk->items[context.backtrack_chunk->count - 1];
+            context.text_start = backtrack_item->text_start;
             SRE_DISCARD_BACKTRACK(&context);
             SRE_RESTORE_MARKS(&context);
             goto backtrack;
@@ -4356,12 +4363,16 @@
     TRACE(("|%p|%p|BACKTRACK ", context.pattern_ptr, context.text_ptr));
     switch(context.backtrack_chunk->items[context.backtrack_chunk->count - 1].op) {
     case SRE_OP_ASSERT:
+    {
         // Assert subpattern.
         // <ASSERT> <skip to end> ... <END_ASSERT>
+        SRE_BACKTRACK_ITEM* backtrack_item = &context.backtrack_chunk->items[context.backtrack_chunk->count - 1];
         TRACE(("ASSERT\n"));
+        context.text_start = backtrack_item->text_start;
         SRE_RESTORE_MARKS(&context);
         SRE_DISCARD_BACKTRACK(&context);
         goto backtrack;
+    }
     case SRE_OP_ASSERT_NOT:
     {
         // Assert not subpattern.
@@ -4369,6 +4380,7 @@
         SRE_BACKTRACK_ITEM* backtrack_item = &context.backtrack_chunk->items[context.backtrack_chunk->count - 1];
         TRACE(("ASSERT_NOT\n"));
         context.pattern_ptr = backtrack_item->pattern_ptr;
+        context.text_start = backtrack_item->text_start;
         context.text_ptr = backtrack_item->text_ptr;
         SRE_RESTORE_MARKS(&context);
         SRE_DISCARD_BACKTRACK(&context);
@@ -5121,19 +5133,21 @@
     if (look_literal != NULL)
         look_ahead = look_literal;
 
-    context.text_start = (SRE_CHAR *)state->beginning;
+    context.text_beginning = (SRE_CHAR *)state->beginning;
+    context.text_start = (SRE_CHAR *)state->start;
     context.text_end = (SRE_CHAR *)state->end;
     context.text_ptr = (SRE_CHAR *)state->start;
 
     while (context.text_ptr <= context.text_end) {
         TRACE(("|%p|%p|SEARCH\n", pattern, context.text_ptr));
         if (SRE_LOOK_AHEAD_ONE(&context, state, look_ahead)) {
-            state->start = state->ptr = context.text_ptr;
+            state->start = state->ptr = context.text_ptr++;
             status = SRE_MATCH(state, state->pattern_code);
             if (status != 0)
                 break;
         }
-        context.text_ptr++;
+        else
+            context.text_ptr++;
     }
 
     return status;
=== modified file Modules/sre.h
--- Modules/sre.h 2008-09-25 18:21:17 +0000
+++ Modules/sre.h 2008-09-30 00:30:31 +0000
@@ -69,6 +69,7 @@
 typedef struct SRE_BACKTRACK_ITEM {
     int op;
     SRE_CODE* pattern_ptr;
+    void* text_start;
     void* text_ptr;
     int index;
     int repeat_counter;