fill-paragraph for indented lines

[Ones Self]

Hi,

I'm trying to get fill-paragraph to no fill lines that start with a tab:

        This is the
first line.
        Here is some more
text.

If I use fill-paragraph on this text I get:

        This is the first line.  Here is some more text.

what I want is:

        This is the first line.
        Here is some more text.

which means: treat indented lines as a beginning of a new paragraph


thanks