From within the Guest OS (WinXP), if a file that ends in 'inp' is created/renamed/modified in a shared directory then the date information on that file is mangled.
For example, a file named 'test.inp' and a file named 'testinp' both exhibit this behavior. However, there is no problem with a file named 'inp.txt'
From the Guest, the date of the file appears to be "Thursday, July 21, 2185, 6:34:33 PM"
From the Host, the date of the file appears to be "2185-07-21 19:34" (In some cases, the date has appeared as May 1913, however this is not consistent and may involve some other program operating on the file after the date is corrupted)
If a file that ends in 'inp' already exists in the shared directory, then its date is not modified. However, an 'inp' file that is created in the Host OS while the Guest OS is running will be modified when the Guest OS refreshes its file view.
The behavior is consistent and repeatable.