Maybe I misread his intention then. I was under the impression that he wanted to write portable code between the PC and the PocketPC so that he wouldn't have to have separate code for each and surround the code in #ifdefs. Using TCHAR arrays and the "tchar" version of the library routines (such as _stprintf) will do this and they are designed exactly for this purpose.
TCHAR outStr[32];
_stprintf(outStr, TEXT("%d"), countdown_seconds);
That code will work on the PocketPC and the PC. No muss - no fuss. That is what I thought he was asking how to do.
Sometimes I find the most difficult part of providing help to people on this site is actually understanding what they are trying to do.