I don't know if I am in error, but ':set lines=999 columns=999' from .vimrc does not work for me under KDE 3.5. It works in ex mode, after everything is loaded, but not from the .vimrc file (and yes I am using gvim). There are also some notable strange effects:
au GUIEnter * set lines=999 columns=999 seems to really make gvim think there are so many columns and lines: word-wrap is turned off and command line disappears, but it resizes the gvim's window ok. the only thing that works for me is: au CursorHold * exe ':set lines=999 columns=999 | au! CursorHold', which does the resizing after a delay, but sometimes even this produces the aforementioned strange effect. In short, under KDE, :set lines=999 columns=999 works for me after everything "settles down", but not before. I am using gvim 7.0.17.