There are many formats you can choose from, see example below
450 data _null_;
451 x='7jan2012'd;
452 put x yymm7.;
453 put x yymmc7.;
454 put x yymmd7.;
455 put x yymmn6.;
456 put x yymmp7.;
457 put x yymms7.;
458 put x yymon7.;
459
460
461 run;
2012M01
2012:01
2012-01
201201
2012.01
2012/01
2012JAN
NOTE: DATA statement used (Total process time):
real time 0.00 seconds
cpu time 0.01 seconds