Hi.
Let's see if I can clarify this for you a little bit.
First of all, note that what HP calls "trunking" has nothing whatsoever to do with VLANs, it's Ling Aggregation. HP talks about VLAN tagging.
Assume that you have 2 VLANs configured to the 2524: VLAN 1 with ports 1 - 10 and VLAN 2 with ports 11 - 20. All these ports must be UNTAGGED for the VLAN they belong to and NO for the other VLAN.
HP VLANs are strictly port-based, so any device you connect to port 5 will automatically be a member of VLAN 1. The devices in different VLANs must be in different subnets, however, say you have VLAN 1 devices in 10.10.1.0 and VLAN 2 devices in 10.10.2.10. I actually don't know what happens if you connect a device with VLAN 1 IP address to VLAN 2 port... maybe that's something to be tested tomorrow :-) You shouldn't do it, anyway.
Then you want to make an uplink to the Cisco device with say, port 24, and you make that port a TAGGED member of both VLANs.
... and that's really all there is to it on HP side. Then the port will carry the info from both VLANs.
I'd suggest you check out the Management and Configuration guide of 2524, you can find that from
www.hp.com/rnd under Technical Support and Manuals. That's a very good source of information and has good config examples as well.
HTH,
Arimo