Bash-completion has errors on Debian Squeeze, and while they've been fixed, it'll be forever until we get it officially backported. (See http://ask.debian.net/questions/why-did-bash-compleation-expand_tilde-stoped-working-in-squeeze)
I have taken the liberty of using the commit where it was fixed, and making a simple patchfile. (See http://anonscm.debian.org/gitweb/?p=bash-completion/bash-completion.git;a=commit;h=ccbf141e13eaa98d6a8721ae015a5504654424cb)
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