Format Phone Number and Arbitrary Mask does not work

Hi. I am using Acrobat Pro 9. When I try to format a text field by clicking on Special and then Phone Number, the formatting works fine on my computer but when I send the form to co-workers and they type in the phone number, there is no formatting (xxx) xxx-xxxx. Next I tried to do an abritrary mask and the same thing happened, it works on my computer but not on my co-workers. Please help...This one is making me nuts!
 
Thanks,
 
Jeff