Hello,
100 Mbps media is not supported on SUP 7L-E.
"The Supervisor Engine 7L-E has four uplink ports. Ports 1 and 2 support either 10GBASE SFP+ transceivers or 1000BASE SFP transceivers. Ports 3 and 4 support only 1000BASE SFP transceivers. There are restrictions on the use of the uplink ports in both single supervisor engine and redundant supervisor engine configurations and both 10-G and 1-G operation."
Table 2.
http://www.cisco.com/en/US/docs/switches/lan/catalyst4500/hardware/configuration/notes/OL_25750.html