@firsikov:
Using regex can be difficult and tricky at times. Consider another way to accomplish the same thing, without changing the HTML code.
What you seem to want is to control the look of text within a particular type of blockquote. Consider using CSS contextual styles:
Quote:
|
blockquote.email p.text {put your desired styles here}
|
This form of style selector will only affect the precise text you want to change.