Polycom V500 Release Note page 21

Release Notes
V500 and VSX systems, version 8.5
Feature Limitation
Interoperability Systems behind Fortinet firewalls configured to use their
Fortinet H.323 service will not connect if the caller is configured to
use AES encryption.
Interoperability No content can be sent or received when the V500 or VSX
France Telecom system is connected to France Telecom eConf.
The V500 or VSX system is unable to connect to France
Telecom eConf 3.5 when H.239 is enabled.
Interoperability H.239 works with TANDBERG MXP systems, but H.239
H.239 interoperability with other systems is not supported.
Interoperability H.460 does not work correctly with a Check Point firewall.
H.460
Systems may have no video when calling out from behind a
Fortinet firewall to a provider endpoint.
Interoperability In H.323 multipoint calls using AES encryption, with a VSX
iPower system as the MCU and iPower and PVX systems as
endpoints, iPower will not transmit video if PVX is the second
endpoint. To avoid this issue, call the PVX system first.
When an iPower dials into a VSX 7000e MCU and another
VSX system joins the call, the iPower will disconnect. To
work around this issue, connect the iPower as the second or
later participant in the conference.
Interoperability Systems behind Linksys BEFSR41 will not receive calls.
Linksys
Use of the V500 or VSX system with a wireless network
bridge behind a Linksys WRT54G wireless broadband router
may be problematic and has not been qualified. If
connectivity problems arise, ensure that the WRT54G has
the latest available firmware installed on it.
Linksys RV082 does not work in H.460 calls with VSX
systems and V
Linksys BEFSX41 routers may reboot in calls that use H.460.
VSX systems running version 8.5 in UPnP setups with
Linksys (and maybe other) NAT boxes cause video calls to
stop connecting.
2 IU™.
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