literate haskell

Why is it necessary to leave a blank line between comments and code? I'm using LaTeX in my lhs files, with the code inside a verbatim environment, and I'd rather start writing my code right after the \begin{verbatim}. I'd also like to know if anyone as changed is xemacs configuration file in such a way that is easy to change from haskell to LaTeX mode from within lhs files, and compile (latex compile) them. I always have to change to latex mode, the change the syntax highlight, and even then I can't compile the from the included lhs files - it always calls view instead of compile, even if I specify the correct Master file. Thanks in advance J.A.