Has anyone had issues or success in making a phone number with letters in place of numbers work in Apple's iOS mail app?

Here's the sample code with (fake phone number):

<a href="tel:+1-888-555-2222" style="text-decoration:underline; color:#5e2b94"><span style="text-decoration:underline; color:#5e2b94">1-888-555-ABBA</span></a>

When you try to click the phone number, the code works fine in the Gmail app but not in the iOS default Mail app.

Thanks!
John