Custom WsdlBehaviourExtension in assembly with version which increases on each build

Custom WsdlBehaviourExtension in assembly with version which increases on
each build

I have a custom wsdlbehaviorextension which is working fine, here's my
config:
<behaviorExtensions>
<add name="MyName" type="NS.MyType, MyAssembly, Version=1.0.0.0,
Culture=neutral, PublicKeyToken=null" />
</behaviorExtensions>
I've updated MyAssembly versión to 1.0.* so that it increases on each build.
How should I update my web.config so that it detects the new version on
each build?
I've tried:
<behaviorExtensions>
<add name="MyName" type="NS.MyType, MyAssembly" />
</behaviorExtensions>
But didn't work.
Thanks