[TYPO3] relative path mistaken

[Arpad Muranyi]

hi,

i have a TYPO3 installation which is not the the root, so i can reach it 
like www.mydomain.com/dev

TYPO3 itself works fine, but i have problem by applying eg. relative 
paths in TS, such as /fileadmin/etc.jpg and it looks for a file here: 
www.mydomain.com/filedamin/etc.jpg instead of 
www.mydomain.com/dev/fileadmin/etc.jpg

what shall i setup to achieve good results?

arpad