RFORCE doesn't allow negative rotational acceleration

[victorkemp]

Input:

SOL 101
CEND
SPCFORCES = ALL
LOAD = 1
BEGIN BULK
GRID           1       0     0.0     0.0   0.0         0       3
GRID           2       0     2.0     0.0   0.0         0
CELAS2         1   3.0+6       1       3       2       3
RFORCE         2       0       0     0.0     0.0     1.0     0.0        +
+           -1.5
CONM2          2       2       0     7.0
LOAD           1     1.0     1.0       2
ENDDATA 

F06 says:

ECHO: loadb RFORCE         2       0       0     0.0     0.0     1.0     0.0        +                                                                                                                                                                                       
ECHO:  nextc +           -1.5                                                                                                                                                                                                                                                
 *ERROR  1194: NEGATIVE GRID ID NOT ALLOWED ON RFORCE           ENTRY. VALUE IN FIELD   2 OF CONTINUATION ENTRY NUMBER   1 IS = -1.5            

It works OK in Comlab.