Hi Necdet, thanks for your help,
I have the similar codes as yours, but my problem is that my javascript function can not be recognized at all.
I created a simple javascript function to see if it can be called and bound it with OnChange event of telephone1 field, but when I tested it to enter the number on that field, I got error below:
One of the scripts for this record has caused an error. For more details, download the log file.
ReferenceError: xxxxx is not defined at eval (eval at RunHandlerInternal
Please let me know if there is any thing wrong with my case, thanks