This needs to be partly ported and mostly redesigned to 3.0. This is likely difficult.

Bugzilla/GNOME.pm needs to be ported as well

Note: instead of searching the database, the functions should be parsed when comments are added. Then an MD5 should be taken from this and stored in a column. Either in longdescs, or in another table, referencing the comment in longdescs.

Per problems with attach_data (was split up from attachments table to increase query speed), the other table probably makes sense.

The parsing should be done in AppendComment() in create() in Bugzilla/Bug.pm. Further, checksetup.pl should parse existing comments and fill the table/column. See extensions/gnome/code/install-update_db.pl.

Simple-dup-finder should first check if a stack trace can be found. If so, use the MD5 column/table. If not, use full text indexing.
Note: We'll be using Postgresql (likely), so needs to be checked if Pg FTI works when dumping the entire comment in there.

If you are interested, please say so. I can add more detail if needed.