Advanced Guestbook stopped working for no reason.

I had everything working just fine for about a week. Then, for no apparent reason, it just stopped working.

Now, I get a whole page of "parse errors" instead. Half the time I try to go to the admin page, I also get parse errors, but sometimes I can actually login. But 100% of the time, the guestbook index page displays errors.

The errors are like this:

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(132) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(153) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(132) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(153) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(153) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(132) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(153) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(132) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(153) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(117) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(132) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(153) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(117) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(132) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(153) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(117) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(132) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(153) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(117) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(132) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(153) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(52) : eval()'d code on line 5

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(53) : eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/lib/gb.class.php(54) : eval()'d code on line 2

When I get errors trying to access the admin.php page, this is what those look like:

Parse error: parse error in /home2/.../guestbook/admin.php(207) : eval()'d code on line 5

Parse error: parse error in /home2/.../guestbook/admin.php(20

: eval()'d code on line 1

Parse error: parse error in /home2/.../guestbook/admin.php(209) : eval()'d code on line 2

I never changed anything for this to start happening. What could it be?

Please help!

Thank you.