With this patch, things seem to work with a Heimdal client and MIT KDC. * checksum_length.c (krb5_c_checksum_length): Handle trunc_size. To generate a diff of this commit: cvs diff -r5.143 -r5.144 krb5/src/lib/crypto/ChangeLog cvs diff -r5.3 -r5.4 krb5/src/lib/crypto/checksum_length.c