configuration table permanent storage?

[Marc Murphy]

Once you use a configuration directive to store some values in a module's configuration table, is there any way to change them after that?

When there is a request I grab the values I initally stored in the configuration table (which I believe are stored only once when httpd starts and the configuration directive is encountered)
I grab the values using $cfg= $r->Apache::ModuleConfig($r, Modulename).

Now if I make some changes
i.e. $cfg->{key}=newvalue
that's fine for the request currently going on. Then for the next request the newvalue is replaced by the initial value.
Is this how it's supposed to work...i.e. the way you setup the module's config table is permanent? Can I get the change to stick somehow?