"Is A Date" Question

[Dom]

I go with a question about "is a date" problem.

As my stack goes with customized date format, I want to insure that the
user (me, for instance) entered a valid date...

I may be wrong, but it seems that the question " is a date" is true ONLY
with the standard US-english date format, i.e.

09/24/03 > true
(according my system preferences) 2003-09-24 > false!

Sure, it is possible to write a little function which translate from y
custom date format to the standard one -- but I have to KNOW exactly the
custom date format; therefore it is not possible to write a handler
valid in all circumstances...

Any idea?

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