sortname for editor messes up crossrefed entry

sortname for editor messes up crossrefed entry

In the .bib-file there are two relevant entries -- the crucial point is
sortname, for (by using prefix=true) I want to print De Jong, Irene J. F.,
René Nünlist und Angus M. Bowie but sort the collection without the
"von"-part of de Jong's name:
J ohnstone, Mark A. book
De J ong, Irene J. F., Renee Nünlist und Angus M. Bowie collection
K amtekar, Rachana article
@Collection{JongNuenlistBowie:Narrators,
editor = {Irene J. F. de Jong AND Ren{\'e} N{\"u}nlist AND
Angus M. Bowie},
sortname = {Jong, Irene J. F. de AND Rene{\'e} N{\"u}nlist AND
Angus M. Bowie},
gender = {pp},
title = {Narrators, Narratees, and Narratives in Ancient
Greek Literature},
booktitle = {Narrators, Narratees, and Narratives in Ancient
Greek Literature},
shorttitle = {Narrators},
language = {english},
year = 2004,
titleaddon = {Studies in Ancient Greek Narrative, Volume~1},
booktitleaddon = {Studies in Ancient Greek Narrative, Volume~1},
series = {Mnemosyne. Supplementum},
number = 257,
publisher = {Brill},
location ={Leiden AND Boston}
}
@InCollection{Morgan:PlatoNarrative,
author = {Kathryn A. Morgan},
gender = {sf},
title = {Plato},
language = {english},
crossref = {JongNuenlistBowie:Narrators},
editor = {Irene J. F. de Jong AND Ren{\'e} N{\"u}nlist AND
Angus M. Bowie},
year = 2004,
booktitle = {Narrators, Narratees, and Narratives in Ancient
Greek Literature},
booktitleaddon = {Studies in Ancient Greek Narrative, Volume~1},
series = {Mnemosyne. Supplementum},
number = 257,
publisher = {Brill},
location = {Leiden AND Boston},
chapter = 28,
pages = {357-76}
}
Now, biblatex uses the sortname of the collection also for the names of
the author in a crossref- (not xref-)entry and prints Morgan, Kathryn A.
2004 »Plato«, Englisch, in de Jong u. a. (2004), Kap. 28, S. 357–76 after
the De Jong-Collection and before the article by Kamtekar.
J ohnstone, Mark A. book
De J ong, Irene J. F., René Nünlist und Angus M. Bowie collection
M organ, Kathryn A. InCollection
K amtekar, Rachana article
How can I use sortname for the editors but not for the authors in a
collection?
BTW: I use tlmgr with the latest updates, biber, and biblatex with the
following option: \usepackage[style=philosophy-modern, sortlocale=de,
sorting=nyvt, babel=hyphen, alldates=terse, annotation=true,
useprefix=true, pagetracker=true, volnumformat=default, datezeros=false,
pagetracker=spread, bibencoding=auto, publocformat= loccolonpub,
backend=biber, citetracker = constrict, ibidtracker=constrict,
opcittracker=constrict, idemtracker=constrict,
relatedformat=parens]{biblatex}