Error in Tiny Tiny MCE regarding text-decoration in hyperlinks

Hi everybody.
First of all, thanks for this wonderfull editor!

Now the problem:
I found some undesirable behaviour in Tiny Tiny MCE. I am not sure if it is an error or there is a way to avoid it.

I copy a code like this in my Tiny tiny MCE ("pure" html mode)

<a style="text-decoration: none;" href="http://example.com" target="_blank">TEXT</a>

If them I click two times the button "text-rich-editor", i.e, I go in the WYSWYG editor and again in the html editor, then I get the next mode

<a href="http://example.com" target="_blank">TEXT</a>

The editor removes the text-decoration of the hiperlink.

Is there a way to avoid it?

Thanks in advance!