stems up?

[Ivo Bouwmans]

Hallo all,

I try to get both upper notes (e'') in the following fragment to have 
their stems upward.
Nor voiceOne nor stemUp seems to work:


{
  << { \voiceOne e''2. } { \voiceTwo a'2~a'8[ b'] } >>
  << { \stemUp e''2.\fermata } { \stemDown b'2.\fermata } >>
}
\version "2.12.1"  % necessary for upgrading to future LilyPond versions.


What am I doing wrong?
(I might be doing it in a complicated way, anyway.)

Thanks for any ideas!
--
Vriendelijke groeten,  =  Best wishes,  =  Afablajn salutojn,

Ivo


www.ivo.bouwmans.name