[mathattack]

The best way to combat ageism is to look for hiring managers that are as old or older than you. It does limit your search a little, but you have to limit the universe of potential positions in some way. Enterprise roles tend to have less ageism than consumer ones.

A couple other thoughts:

1 - When you have too much experience for the job, employers are concerned that you're desperate, and will leave when a better opportunity comes by. If you connect with someone senior in the organization, you can negate this. (They'll have other uses internally for your skills)

2 - Smaller companies don't like hiring people from bigger companies. You have to push hard on technical skills and show that you're flexible. Also don't oversell the brand names of your employer. Names like Cisco and IBM mean something to big corporates, but less in the startup world.

3 - Look for ways to leverage multiple areas of your background. For more experienced people, it can help to look for jobs that are asking for 2 or 3 disparate skills that are less likely to be found in a junior person. For example, "I'm looking for someone who has done both consulting management and front office banking" In your case, telecom + testing + support engineering + architecture is unique enough that there are jobs where you will be differentiated.

4) The more senior you get, the harder it is to find the right job. It's a matching problem. There's either 0 or 1 jobs at each company for your position, but also much fewer candidates.