GROMACS

This is about starting simulation from a 4.5.5 tpr-file using 4.6 (or 4.6.1) that contains dihedral restraints.
I have made a small test-system with a dialanine-peptide in vacuum to reproduce the issue.
The system contains one single dihedral restraint (with arbitrary but reasonable values of phi, dphi, etc...)

System was prepared like this:

$grompp -f md.mdp -c conf.gro -p topol.top -o md.tpr

Checking that it is there:

$gmxdump -s md.tpr |grep DIHRE
Reading file md.tpr, VERSION 4.5.5 (single precision)
        functype[166]=DIHRES, label=0, power=   1 phi= 1.20000000e+02, dphi= 3.00000000e+01, kfac= 1.00000000e+00)

Now running this in 4.5.5 works fine, but starting it in 4.6 (or 4.6.1) gives me an error.

$ /Users/per/source/gromacs-4.6.1/build/src/kernel/mdrun -v -deffnm md
Reading file md.tpr, VERSION 4.5.5 (single precision)

-------------------------------------------------------
Program mdrun, VERSION 4.6.1
Source code file: /Users/per/source/gromacs-4.6.1/src/gmxlib/symtab.c, line: 136

Fatal error:
symtab get_symtab_handle 1051260126 not found
For more information and tips for troubleshooting, please check the GROMACS
website at http://www.gromacs.org/Documentation/Errors
-------------------------------------------------------

Taking away the restraint allows me to start the run in 4.6.1, and also reformatting the [ dihedral_restraint ] section to comply with 4.6 works.

Thanks