Combine rests from two voices

[Erik Ronström]

Hi!

I am writing a single staff with two voices, using \voiceOne and \voiceTwo. Is 
it possible to have rests common to both voices to be combined into "single 
voice rests"?

Of course I could do like 

<<
  \newVoice = "one" { \voiceOne a4 b c d }
  \newVoice = "two" { \voiceTwo a4 b c d }
>>
r2 r4
<<
  \newVoice = "one" { \voiceOne a4 b c d }
  \newVoice = "two" { \voiceTwo a4 b c d }
>>

but it is not a very practical solution.

Regards
Erik