CFileDialog -- no files shown

In MSVC 1.52, when I put up an File Save As dialog with at suggested file name, the user sees all the files with the specified extension. The same code under VC 4.0 has a blank list box. However, if I don't suggest a file name, the files show up again.

Is this how it's supposed to work? I like the 1.52 behavior better.

Any ideas?

CFileDialog dlg (FALSE, "sif", LPCSTR(csSifName),
OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT,
"Interchange Files (*.sif) | *.sif | All Files (*.*) | *.* ||");