maximum number of sessions for port mirroring on 4510

[helpwithcisco]

Are you only able to have two sessions for port mirroring on a Cisco 4510?                  

[Reza Sharifi]

You can configure up to two simultaneous SPAN  sessions containing ingress sources and up to four simultaneous SPAN  sessions containing egress sources. Bidirectional sources count as both  ingress and egress. RSPAN destination sessions count as a session  containing an ingress source.

Config guide:

http://www.cisco.com/en/US/docs/switches/lan/catalyst4500/12.2/31sg/configuration/guide/span.html

HTH