Is there a way to access variables across different script units w/out using proj vars?

UNIT1 script contents:

'USEUNIT Unit2

public sMessage1

Sub sSampleSub1

  sMessage = "Hello"

  sSampleSub2

End Sub

UNIT2 script contents:

'the below line HAS TO BE here otherwise it wont work

'USEUNIT Unit1        

Sub sSampleSub2

  msgbox sMessage

End Sub