Share cache between to web application

I have 2 web applications A and B, A is used by administrators to manage directories and security roles ...and B is used by other users to ... In the web app B when the user is logged in, we load infomations related to the user in the cache. We have encoutred some issue when the admin update some date using the web app A, these informations are not reflected in the web B because the data is cached in the memory. Is there any way to update share the cache between the apps without creating a new web app or a WCF service ?

Thanks for you help, Bilel