While upgrading the cygwin environment, the PostreSQL database has been upgraded too, but not ipc-daemon [1], odbc-driver [2] and pgadminII [3]. So I had to fetch the latest releases and add them too. Now it works again.
[1] http://www.neuro.gatech.edu/users/cwilson/cygutils/cygipc
[2] ftp://ftp.us.postgresql.org/odbc/versions/msi/
[3] http://pgadmin.postgresql.org/downloads/