Hi,
attached you'll find a simple but so far effective filter to remove multi-line comments from SQL source. I've used this to pre-filter sql source before submitting it to the <sql> task, which would fail if there's an embedded GO withing the multiline comment. Maybe useful for inclusion in nantcontrib, possible as part of the sql task. Source based on one of the existing NAnt tasks, license (afaic): public domain.
SqlCommentFilter