components of variance question

[SMELGAR at UCRVM2.BITNET]

Could anybody please tell me which statistical package can I use to obtain comp
onents of variance of a hierarchical analysis of variance with one covariable?

  The main problem is that the analysis is unbalanced, therefore it is
 very difficult to obtain the estimates of components of variance by hand.

  I will appreciate any help.  My e-mail address is
  SMELGAR at UCRVM2

Thank you,
             Sergio Melgar
             Escuela de Biologia
             Universidad de Costa Rica