end of line comment moves on code reformat

I don't want to report this as a bug since I think its my own error but I haven't been able to find the setting to stop line comments in Scala from ending up on the next line after a code reformat.  E.g.,

  final val invalidToken = "invalid"    // Token that will never be used

after code reformat ends up as:

  final val invalidToken = "invalid"
  // Token that will never be used

Advice on the setting I need to enter to fix this would be most welcome.

  -ljr

IDEA 10.0.1
Build #IU-99.32
JDK 1.6.0_22
Scala Plugin 0.4.345