http://groups.google.com/group/AGABBIP/browse_thread/thread/bc3ab7dc86829adc...
http://danial.pixelsndots.com/archives/386
"Pakistan Blocks Wikipedia
After Blocking the dirty dozen, Pakistan bans Wikipedia. The Government has gone totally mad and someone needs to stop them from this crazyness. Atleast three different ISPs failed to open Wikipedia. "
According to http://help-pakistan.com/main/dont-block-the-blog/, the block has now been lifted.
See http://mail.wikipedia.org/pipermail/textbook-l/2006-March/002491.html for a press release forwarded to the Wikibooks list.
General information on blocks in Pakistan: http://pakistan.wikia.com/wiki/Internet_Filter_Status
http://meta.wikimedia.org/wiki/Wikimedia_projects_blocks still only mentions China.
Angela.