B737-800
Air Traffic Control Fully Certified
Confusion
ATC Issue All Types; Conflict Airborne Conflict
General None Reported / Taken
Procedure
Weather north of DEN and the aircraft were deviating.  I took the hand off on Aircraft X and I noticed RADAR histories on the west side of the Data Block.  I picked on the target and Aircraft Y Data Block appeared due north climbing to 21;000 FT.  Aircraft X was climbing up also just east of the Aircraft Y and said she was deviating to MBW...Aircraft X's Data Block stated DR/MBW in the fourth line; which means deviating right; MBW when able.  So Aircraft X turned direct to MBW heading right for Aircraft Y.  I immediately turned the Aircraft X to a H360 and expedite their climb through 22;000 FT with clearance up to 32;000 FT.  I was thinking that I may have deviated DEN Approach's airspace; but had I done nothing Aircraft X would have run over Aircraft Y.  My question is who was separating the two aircraft and what separation standards were they using?  DEN approach only needs 3 miles and 1;000 FT; but ZDV needs 5 miles and 1;000 FT.  Recommendation; keep positive control of aircraft.  Issue clearances that guarantee the needed separation.
ZDV Controller described a weather deviation event when the separation required was questioned because both terminal and enroute procedures were involved.