In the other semi final, extra time was needed to separate the sides before Jordanstown out half Gareth Kennedy ensured it would be an all Ulster final with the winning penalty four minutes from the end.
Full back Sean Madigan got Limerick off the mark with a straightforward penalty on 17 minutes. Jordanstown grabbed the lead on the half hour when centre Gareth Kennedy sprinted through a gap in midfield to touch down close to the posts. His brother Neil converted.
A try by right winger Paul Gleeson, which Madigan converted, gave Limerick a 10-7 lead at half time. The only score of a scrappier second half was a huge penalty by Neal Kennedy which went over with the help of the left upright.
Gareth Kennedy, then took over the kicking duties, and after exchanging penalties with Madigan to leave it at 13 points each, he made no mistake when a Limerick forward was penalised at a ruck just outside the 25 to give Jordanstown victory.