Resolution:
TIBCO does not ship DBG or PDB files for any of its products (so this policy issue is not specific to Smart* products).
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From Microsoft: http://support.microsoft.com/kb/121366

The .PDB extension stands for "program database." It holds the new format for storing debugging information that was introduced in Visual C++ version 1.0. In the future, the .PDB file will also hold other project state information. One of the most important motivations for the change in format was to allow incremental linking of debug versions of programs, a change first introduced in Visual C++ version 2.0.

The .DBG extension stands for "debug." The .DBG files created with the 32-bit NT toolset are in the Portable Executable (PE) file format. They contain sections with COFF, FPO, and in some cases Codeview information. The Visual C++ integrated debugger can read .DBG files in this format, however it ignores the COFF symbol sections and looks for Codeview information.
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