[Baypiggies] How to verify if a string is properly encoded in utf-8 ?

[Krishna Srinivasan]

Greetings.

A quick question. How can I verify if a given
string is properly encoded in utf-8 ?

The use case is this - I have a web form that
I send with the charset set to utf-8. But it
is possible that the user might change the
encoding and hence when the form gets submitted,
a different character might get back to me.

Thanks,
Krishna.