The workaround of using the syswow64 version of cmd does not fix this problem with Vista x64:

C:\mozilla-build\msys\bin>c:\windows\syswow64\cmd.exe
Microsoft Windows [Version 6.0.6000]
Copyright (c) 2006 Microsoft Corporation.  All rights reserved.

C:\mozilla-build\msys\bin>bash
bash-2.04$ ls
      0 [main] bash 4592 sync_with_child: child 380(0x1B8) died before initialization with status code 0x0
    228 [main] bash 4592 sync_with_child: *** child state waiting for longjmp
bash: fork: Resource temporarily unavailable
bash-2.04$

James
--
main(c,r){for(r=32;r;)printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}