There's not a direct way to search through Subversion commit messages, unfortunately.
If this is something that you need to do frequently, then I definitely recommend setting up some sort of tool that indexes commits as they are made and keeps cross-referencing information in a database (we've used trac for this). I'm not familiar with Jira, it may have something like this available.
Another option is to write a script that pulls the complete repository log and parses it to look for a reference to a particular ticket. There are Subversion library bindings for most popular scripting languages that should make this fairly straightforward (pull a log and for each revision, search the commit message for a regular expression matching your ticket reference format, and print out the revision number if a match is found). This may take a long time to run as your repository grows larger, so I don't recommend this approach unless this is only something that you need to do once or twice.