Note that there is some number of people who feel pretty strongly about obfuscating their age. I'm not sure what to feel about it personally but it's understandable.
As one of the other replies has stated that trimming the older stuff from your resume can help. I took a variation on that by going into detail with jobs for the last 10 years or so and having a simple list of other places I've worked and what the job titles were. There's also a linkedin url which has the expanded version if the reader is interested in going back more but it let me keep my resume to a single page, single sided, summery of the "professional me".
I started getting better responses when reduced my work experience by 7 years ) It also let me remove some obsolete junk that interviewers never heard of ))
