pre-run script is not executed correctly

I have a short pre-run code in ADEXL, like this,

ocnxlLoadCurrentEnvironment( ?noAnalysis t)
printf( ">>>>>>>>>>>>>>>>>>>>>>> proc = %s, vdd = %L\n" desVar("proc") desVar( "vdd"))
if( (desVar("proc") == "ss") then
      ocnxlUpdatePointVariable("vdd" sprintf( nil "%L" 2))
      printf( "-----------------------------I'm, SS\n")
else if( (desVar("proc") == "ff") then
          printf( "-----------------------------I'm, FF\n")        
          ocnxlUpdatePointVariable("vdd" sprintf( nil "%L" 0.8))
       else
         printf( "-----------------------------I'm, TT\n")
         ocnxlUpdatePointVariable("vdd" sprintf( nil "%L" 1))
       )
)

I have set the variable "proc" to be "ss", and "vdd" to be 9, but the pre-run code doesn't execute the if conditions correctly and always jump to the last else and set the vdd to be 1.

if I replace the  condition (desVar("proc") == "ss") with (2>1), the following statement is executed.

 Anyone knows why?

 Thanks!