No problem...
Open the DosBOX.conf file in notepad and scroll all the way to the bottom.
Everything you write there will be loaded when DosBOX is loaded.
As an example, this is what I have in mine...
Code:
[autoexec]
# Lines in this section will be run at startup.
mount c l:\dosgames
mount d d:\ -t cdrom
c:
cls
Edit: Sorry mate, you must have posted while I wrote...