I did the same and didn't have any ill effects. I would suggest getting PermissionsBukkit along with it.
Check this thread for more help.
http://forums.technicpack.net/index.php/topic,83.0.html
Re: ۞ TekkitCraft ۞ Currently also with Herochat (more to come at a later stage)
IGN: JonnyDerp
AGE:20
PREVIOUS SERVERS: Many others. Can't remember them all but the last one was obsidiancraft I think.