multidb bug for Upgrading to 2.9.2 with multi-db. Solved OK?

Hi.
I 'm trying to upgrade from wpmu 2.8.6 to 2.9.2 using multidb version 2.9.2.
I noticed in my webserver's error log that the queries from the pre_schema_upgrade() which is in /wp-admin/includes/upgrade.php are causing an error.
copy from my log WordPress database error for query DELETE o1 FROM wp_6349_options AS o1 JOIN wp_6349_options AS o2 USING (option_name) WHERE o2.option_id > o1.option_id made by pre_schema_upgrade,

In order to find what is wrong I placed some echos in db.php at the end of analyze_query() and I get
the following
query=DELETE o1 FROM wp_6349_options AS o1 JOIN wp_6349_options AS o2 USING (option_name) WHERE o2.option_id > o1.option_id
table_name=unkown
blog_id=
query_type =
dataset= d

I solved it (this a little help from a friend) by changing the 2 ifs statement for delete in analyze_query() of db.php from

else if ( preg_match('/^\s*DELETE\s+FROM\s+?(\w+)`?\s*/is', $query, $maybe) ) {
to
else if ( preg_match('/^\s*DELETE.*\s+FROM\s+?(\w+)?\s*/is', $query, $maybe) )

Andrew or someone else, can you confirm if this is OK ?

Thanks in advance
Lena