Apple has confirmed that the paste function in Apple Mail has changed.

"This is the expected behavior. When pasting into Mail we perform the 2-step paste. The content is pasted by stripping all the attributes that cannot be modified through the rich edit interface and the result is that you see the pasted content without colors, fonts, etc. We preserve only bold, italic and underline.
If you want to have the original appearance, after paste you need to press undo.
the first undo will restore all the stripped attributes, the second will remove the pasted content altogether."

We have updated Email Signature Pro to conform to this behavior.

What this means for users with IOS 5.0 and higher. If you have text that is only bold, italic or underline, then you should not need to do anything. The update will ensure the text is shown correctly.

If you have text that has color or use a different font other than Arial, you will need to shake the phone to under the formatting changes Apple Mail has made to the signature. While we agree this is not ideal, there isn't much we can do about it since it is the functionality within Apple Mail that affects all apps.

Note that if you are composing within Email Signature Pro or inserting a signature from within Email Signature Pro, the formatting issue does not apply.

We continue to upgrade Email Signature Pro to keep it the best signature app in the iTunes appstore.

Our next upgrade will address hotlinks.