a little yum & a little swig understanding

[cfk]

Gentlemen:
 I am trying to compile gnuradio this afternoon and running into two issues, 
both of which are my naivety with yum.

 The first is that yum on one of my computers is telling me that I have 
enabled gpg keys. So, I run the command that yum indicates, which is

rpm --import public.gpg.key

and rpm replies:

error: public.gpg.key: import read failed.

Next, I try to be able to turn this feature on and off as desired. So, I go 
into /etc/yum.conf and change the line:

gpgcheck=1 to gpgcheck=0 or I comment the line out with a '#'. 

and yum still tells me I need the key even after rebooting the system 
(shouldnt have been necessary, but I am trying everything). So, I guess I 
would appreciate knowing where I am going wrong.

The second issue concerns swig. FC3 installed version 1.3.21 and 
gnuradio ./configure reports that I need swig version 1.3.22. So, the 
question is, how do I go about telling yum that I need the more updated 
version of swig and how do I tell what the version is?

I can see that ./configure has some tricky programmatical way of determining 
the version of swig, but I dont grok it yet. There must be a simple way of 
checking the version of things like swig in a simple straight forward manner, 
and I appreciate it if someone could tell me what that might be.

With Respect, Charles