Binary package hint: openoffice.org
When installing Dapper Beta 2 I chose "English" and "Canada".
This resulted in en_CA being set as my language and openoffice.org setting my default document language to "English (Canadian)".
Unfortunately, there is no spellchecker for Canadian English installed and no clear way how I should go about installing one (there are openoffice.org-l10n-en-gb, -us and -za packages that are already installed but nothing for -ca).
If there is a spellchecker for Canadian English then it should be packaged and installed by default on systems where the user selects "English" in the installer (ie: the language-support-en package should depend on it as it does for -gb, -us, -za). If no such spellchecker exists then the default openoffice.org document language should be set to "English (UK)" as this is the closest approximation of Canadian English available.
Should mention: the obvious outward effect of this bug is that spellchecking is completely disabled per default with no clear way to enable it even though the preferences dialog says that it's enabled. All words (even those that are obviously misspelt) are marked as 'OK'.