Of course the chances of IDs being the same in servers are slim, but it's still better than nothing. I googled it for some time and accidentaly found some patch in a russian site (I know nothing about the Russian language so it might aswell been Chinese). I found a skillgrp.dat. In the textures part of the skillgrp.dat i found icon.etc_potion_blue_i00 and decided that this must be the potion I was looking for. Then i found all the IDs with such a texture and compared with my servers skillname-e.dat. I found many matching IDs, but then one ID didn't have a match. It was 10001 and voilia! It was the one i needed. I copied the whole string with the ID and textures from skillgrp.dat and added it to my servers skillgrp :P This may be confusing, but that's how I did it
P.S. This probably was the post where I got -1 karma, cause I was acting like a jackass ><