Dear Mr. Umpfenbach,
There is another method which mingles with Position and OuterPosition in the active axes.
For more details on the Position and OuterPosition axes properties please check Matlab help. But to summarize, here is a sample code:
If your label is cut off one of the elements of the four-element vector OuterPosition = [left bottom width height] should be modified. If your x label is cut off, then perhaps element bottom is too low. Increase it:
set(gca,'OuterPosition',[left bottom + 0.1 width height])
Note that the vector is in normalized units but you may change that to suit your needs.
Perhaps it might happen that title gets cut off in the process. In this case increase height as well.