Not entirely sure what you mean here, but guessing you mean can she qualify for JB using a combination of Irish PRSI paid and UK contributions.
If she worked here for a minimum of 1 week and this is her first employment in the country there is a good likelihood she could qualify as she will be awarded "Pre-entry credits" for the two years prior to paying her first contribution.
Say she found work now for, say 10 weeks, then was let go. She would sign on and SW would request her UK record to combine it with the Irish one, therefore giving her the required 39 paid contributions. Then, they would award credits for the two years prior to her entry into Irish insurance, thus giving her 52 pre-entry credits for the relevant tax year (2006 for claims made in 2008)