[gmx-users] Dihedral restraints in 4.6 vs 4.5.X

[Per Larsson]

Hi

I anyone aware of any issue starting simulations with 4.6 (or 4.6.1) from a 4.5.X-tpr file with dihedral restraints?
I'm unsuccessful in making them start.

To investigate further, I created a small dialanine peptide in vacuum, with a dihedral restraint. 

Here's the details:

Making a 4.5.5 tpr with a dihedral restraint
$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. 
Is this a know issue, am I missing something obvious, or should I file an issue on redmine?

Thanks
/Per