Possible Duplicate:
How can I display a short chapter name in the header and a long chapter name in the ToC?
I have a quite long chapter title that I break into two lines as follows:
\chapter{long \newline title}
This works well for the title in itself and how it is shown in the table of contents. The problem lies in the header where the title become longtitle (no space between the two words). Would there be an easy way to solve this? I was thinking of using the optional field of the \chapter command but it will also modify what is shown in the TOC (which I am so far happy with).