3Com 3500 on its bridge and port STP states:

bridge port stpState 289
✓ 3500
✓ 9000
✓ 9400
✓ 3900
✓ 9300
bridge port stpState Sets the Spanning Tree Protocol (STP) state for one or more bridge ports.
The selection is effective only if STP is enabled for the system or module.
Valid Minimum Abbreviation
b po stps
Important Considerations
■You can use this command to configure the same setting on m ultiple
ports simultaneously. When you specify multiple port numbers, the
system prompts you to choose the setting and then applies it to all of
the ports.
■The following table explains the forwarding behavio r of a port based
on its bridge and port STP states:
Options
Bridge STP State Port STP State
Port Participates
in STP?
Port Forwards
Frames?
Disabled Disabled No Yes, if link state is up.
Enabled No Yes, if link state is up.
Removed No Yes, if link state is up.
Enabled Disabled No No
Enabled Yes Determined by STP,
provided that the
port link state is up.
Removed No Yes, if link state is up.
Prompt Description Possible Values [Default]
Ports Ports for which you w ant
to control the STP setting
■One or more
valid port
numbers
■? (to display a
port summary)
–
STP state Spanning Tr ee Protocol
state that you assign to
specified ports
■enabled
■disabled
■removed
enabled (factory
default), or current
value