Please use letters only (a-z) in this field. (Greek Chars)

I installed ChronForms and i made a test form.
The problem is when someone tries to write in my form in Greek characters (δοκιμή) appears the following message:
"Please use letters only (a-z) in this field."
How can i fix it?
I don' t want to be translated (i saw the tutorial),i just want to accept Greek Characters.
Also i must inform you that i am new and if it is possible to be detailed.
Thank you.

Hi mythodia,

Turn off 'validate-alpha' in the form Element properties, the validation checks for a-z, A-Z

There is another thread here that talks about validating other alphabets.

Bob

I am sorry for my ignorance but where can i find this?
Also can you post the link of the other thread?
Thanks

The problem solved.
We choose the form we want to edit then wizard edit. After that we choose the fields and we uncheck the "Alphas Only" and Apply.
And we are done.