Toyota Repair: check engine light, toyota tercel, toyota dealership

Question
Hello,
I have a 1999 Toyota Tercel (125 000 km)automatic transmission. Two weeks ago the check engine light came on. My local garage checked the code (PO441)and said that two times out of three the problem didn't reoccur. They turned the light off and told me to come back if it came back on which of course it did a couple of days later.
I brought the car back, they changed a couple of cracked hoses and told me that if this didn't solve the problem I would have to bring the car to a Toyota dealership for a more thorough examination. The light came back on so I went to a Toyota dealership. They checked the code and told me that my best option was to drive with the light turned on since detecting the problem could take a lot of time and be very expensive. Is this really my best option? I have already spent about 130$ and I don't want to spend hundreds more if the problem isn't serious. However I would like to have a functioning check engine light for more serious problems. Is there a probable cause they could check? (I didn't drive with a loose gas cap).
Thanks
Andrew
Montreal, Canada  

Answer
I could not find a listing for a 1999 tercel sold here in the US so I looked up some information for a 98 model, there was actually a service bulletin issued a while back and looking it over it seems that the emission control evap system has a small leak, the solution is to replace the evap canister and the vacuum switching valve(VSV).