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Skype does not support IPv6 at all. EPIC FAIL!!!! Please everybody VOTE FOR IPv6 (<- this link appears to be dead as of January 2012, and the original poll is gone it seems... wonder why that happened...)
FYI the first request for IPv6 enabled Skype date back to 2004!!
Cisco Catalyst 3750
This switch does not support (WS-C3750G-24TS-E) does not support IPv6 access lists on VLANs.
2011-10 Replaced with a WS-C3750X-48T-S and a WS-C3750X-48PF-S.
This one does IPv6 access lists on VLANs. Needs replacing in 2011 anyway. New box might support NAT64?, but I had to use sdm templates for this. In hindside the old one might have supported it as well.
But because that died after powering it off to take it out of service, no way to find that out anymore 
Cisco AP1200
These access points do not support IPv6. Need replacing anyway. The AIR-AP1142N-E-K9 could be a drop-in replacement. Also does N.
December 2011: after successful participation in the Eduroam-as-a-Service from SURFnet/Wentzo wireless, these accesspoints were not needed any more.
I donated them to the System & Network Engineering master education of the University of Amsterdam.
Sharp AR-M276
This copier/printer does not support IPv6 at all.
Could not retrieve e-mail addresses for 'scan to email' after LDAP server went IPv6 only. Hack Work-around: manually put addresses in.
Our big Sharp MX2600n has IPv6 support, so we should get rid of this clunker on the first occasion.
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