Alarm going off and is embarassing

My alarm started gets activates or sounds when the passenger door is opened and it never used to do that. I stop it from going on or making noise by opening the driver side and sometimes that does not work.

Do have an idea as to why that is happening?It is a honda accord EX,1995.

This is about the same post as
http://community.cartalk.com/posts/list/843010.page

This may well be a problem the dealer can best fix. Getting into the security system is complicated without the schematics, and without the car in front of you.

But maybe someone here is an expert on this…