DST US 2007 bug in msvcrt.dll when TZ environment varible is set

The time functions provided in msvcrt.dll are not returning correct values
when TZ environment varaible is set. I installed windos xp DST patch but
still application(written in C++ using VS .NET 2003 ) is unable to get the
2007 DST rules when TZ environment varible is set.
If TZ environment variable is not set, the C++/C application is able to get
the new US 2007 DST rules.
I belive, the msvcrt.dll is not patched to handle the new US 2007 DST rules.

Is any one have any info on this? Please help me.