How to get Wordpress MU / BuddyPress wp_signup meta data

Question

I am trying to get a value from the meta data that is stored in the wp_signups table for a Wordpress MU / BuddyPress installation. I see it's stored in the meta field as s:3:"age";s:2:"25"; ...which is age = 25

I put the information there using $usermeta['age'] = $_POST['signup_age']; in a plugin subscribing the the bp_signup_usermeta filter.

I need to get it back during a function subscribing to bp_before_activate_content.

How can I do this? Whats the function call? (searched documentation to no avail)