Validate a package name string. The second parameter should be the name of the channel validation package, as defined by channel.xml for the current channel. If the package name being validated is the same as the validation package (case-insensitive), then it will be validated using the default rules for PEAR packages.
package name to validate
name of channel-specific validation package
throws no exceptions thrown
final - this method should not be overridden.
This function can not be called statically.