RP has to have a minimum validity of 3 months but the first part isnt correct as I have traveled to dubai 2 times in 2 months since I got my RP here. The requirements are you should have been a GCC resident for least a year and your eligibility to get an on arrival.

FOI :From emirates website:
Visa Issuance:
Holders of a Residence Permit issued by Qatar can obtain a visa on arrival for a max. stay of 30 days, provided:
- residing in a GCC country for at least 1 year; and
- a Resident Permit is valid for at least 3 months on arrival; and
- holding confirmed return tickets. Fee: AED 185.-.
For nationals of India, if profession stated in the passport is: businessman, director, doctor, engineer or accountant.
Additional Information:
All visitors must:
- hold documents for their next destination;
- have sponsor in the UAE to cover their stay. A visa:
- included in an expired passport, combined with a valid passport, can be accepted for travel;
- can be applied for (and issued through internet (e-Visa)), prior to arrival, if arriving at Dubai Airport (DXB).
Minors:
If named in a parent's passport and being of a visa required nationality, the minor is also required to be named in the visa. If the minor is not covered by the visa they will not be allowed entry. Furthermore, the minor can only be accepted for travel provided that they are accompanied by the holder of the passport.

http://www.emirates.com/english/plan_book/essential_information/visa_pas...