so i have a problem with my rear derailleur (shimano 105 circa 2000) squeaking every time i shift up or down although it seems a bit squeakier when i downshift. i took it into the LBS a few months ago (~ 3 mos.) for this problem and they said the cable was dry so they lubed it for me and the squeak went away. now that the squeak is back, i need to know how to go about lubing the cable on my own. can anybody provide me with some instruction? where (precisely) to lube? what lube to use? or was the lube by the LBS just a short term fix for a more serious problem? the same LBS replaced the cables about a year and a half ago. thanks in advance.