Resetting ecu in 05 liberty

[heath_003]

hi all, just wanting some help on how to reset the ecu on an 05 liberty. The car is presenting the problem of engine vibrations when at idle, which is really starting to get to me. the car is still under warrenty but the people at the local subaru are incompetent and do not know how to fix it. it has been there 5 times already, each time they have done everything from changing spark plugs to a complete top engine rebuild. now they have tried everything they can think of they are telling me that it is normal for the car to do that and i will have to live with it. i have taken it to my mechanic, who specialises in subaru's, who says it is a simple - and common problem - in subarus where the ecu needs to be reset, however he does not want to charge me for it as he also believes it should be covered under warrenty (as i agree).
if anyone knows how to do this any help will be great. if it is too difficult i will take it to my mechanic to have it done but would prefer not to pay for it if possible. (please also note that if you are considering buying a subaru from tynan motors please dont, the service does not exist, and there has been a letter written to fair trading commission as a result of their attitude toward a new car purchase - this has been going on since new)

once again, any help would be great
heath