basic recurrency...
I think your 121 recurrent ride qualifies as a BFR under the regs.
You need the 3 landings (to full stop at night) w/i 90 prev days for passenger carriage. Nothing said about the class of aircraft (single/multi).
IFR Currency...must be able to look back 6 mo. and find [6 approaches, VOR tracking & intercepts, and and a hold]. => you can file & fly IFR.
If you can't find that...you have 6 mo. from when you lapsed to satisfy the requirements with a safety pilot (because you can't file/fly IFR).
If you look back 12 mo. and neither is satisied...you need an IPC or Instrument Proficiency Check with a CFII and it needs to be endorsed as such.
Neither the IFR Currency or Landings state Single/Multi (class) requirements. The cheapest way to do it all is...
find a CFII, rent a C172 at night and do your IPC with to full stop landings. Instant IFR/Night/Day Currency.
I've also gotta add, get the book for the aircraft and look at it before going. I've checked out US Airways, United, Airtran folks in a little old cherokee and every one of them has needed some extra time due to the lack of an FMS/INS/Autopilot/ and the visual pitch attitude & speed differences they're overcoming going from a B767 to a PA28.
I'm sure it's a tough wait...what have you been doing for a year out of curiousity. Get any flying job you can and go for Jetblue with your times, especially with the big EMB order out there.
Good luck.