  According to previous spectral analyses of Wolf-Rayet type central stars,
late [WC] subtypes show systematically higher carbon-to-helium abundance ratios
than early [WC] subtypes. If this were true, it would rule out that these stars
form an evolutionary sequence. However, due to the different parameter domains
and diagnostic lines, one might suspect systematic errors being the source of
this discrepancy. In an ongoing project we are therefore checking the [WC]
analyses by means of the last generation of non-LTE models for expanding
stellar atmospheres which account for line-blanketing and wind clumping. So
far, the abundance discrepancy is not resolved. Further element abundances (H,
N, Fe) are determined and compared with evolutionary predictions.
