Problem in opening channel builder .ses files

[johneric]

I used the channel builder to build a Q type calcium channel. I had selected 'Create new type' for 'Selective for ion...' and used the GHK equation. When I tested the channel with a single compartment model, it worked fine. But once I saved it in a session file and tried to load the session file again I kept getting the error message,

[i]nrniv: NonSpecific_ion is not an ion mechanism
in D:/John/PhD/Project/MSP Wolf 2005/Garage/temp.ses near line 15
{genprop.set_data("CaQ", 1, 0, 8, "ca")}
^
ChannelBuildSelectProperties[0].ion_charge"NonSpecific_ion" )
ChannelBuildSelectProperties[0].set_useionstr )
ChannelBuildSelectProperties[0].set_namestr )
ChannelBuildSelectProperties[0].set_data"CaQ"108"ca" , , , , )[/i]

I am surprised because I didn't select 'Non-specific ion' at all. I notice that this problem keeps coming if I choose the GHK option in the channel builder irrespective of the ion.

Can someone please help me with this problem?

[ted]

You may have run into a bug. If so, there is a possibility that it has already been
fixed. What version of NEURON are you using?

[johneric]

I am using Neuron version 5.8.88..

[ted]

I was able to reproduce the problem with 5.8.88. It was fixed in the alpha version I picked
up from the CVS repository late last week. I see that a new set of alpha version installers
is now available; why don't you get one of those from
http://www.neuron.yale.edu/ftp/neuron/versions/alpha/
and see if that doesn't take care of it?

[johneric]

Yes the 5.9 alpha version does take care of it. The bug is not there in the versions prior to 5.7 either. Also I could fix the problem in version 5.8 by interchanging the positions of the following statements in the chanbild\properties.hoc file within the set_data function.

selion(iontype_, $s5)
set_namestr()

thank you