Problem compiling 1B3a under VC++ on NT 4.0 - anyone else seen this?

The library compile runs through several of the sub- projects with only a few warnings and then VC++ gives me the following error and quits:

   Creating library ../../../Bin/wwwrules.lib and object ../../../Bin/wwwrules.exp
HTProxy.obj : error LNK2001: unresolved external symbol _HTAuthFilter
../../../Bin/Debug/wwwrules.dll : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.
msvc_40.dll - 2 error(s), 0 warning(s)

I'm backtracking now to noodle out how VC++ is suppose to know where HTAuthFilter is but if anyone else has already encountered this and knows what's broken, I'd love the help.

I usually work on single level projects so I'm a bit fuzzy how symbols get defined and made visible among sub-projects in a complex project like this.

Dennis Gallagher