strange problem with date validation

[Guest]

Now this one is driving me crazy:
asp.net 2003

I have an ASPX page with a textbox where the user must enter a date. The
textbox has an associated compare validator , operation "datatypecheck", type
"date"

Everything works as expected... except if you input 08/10/2005 (meaning 8
october 2005). In this case, the validator flags this as an invalid date.
Dates before or after this one are accepted.

Note that this is not a d/m/y or m/d/y issue -- 8/10/2005 is valid in either
order

Problem occurs on TWO different installations, and does not occur on others.
Seems to be installation-specific.

Thanks !