diff --git a/mandaye/backends/default.py b/mandaye/backends/default.py
index 0caabd1..10e579a 100644
--- a/mandaye/backends/default.py
+++ b/mandaye/backends/default.py
@@ -95,3 +95,9 @@ class AssociationExample(object):
         return a dict of the association
         """
         pass
+
+    @staticmethod
+    def has_sp_login(sp_login, sp_name):
+        """ Test if a service provider login is present on the databases
+        """
+        pass
diff --git a/mandaye/backends/ldap_back.py b/mandaye/backends/ldap_back.py
index 7c6b0d6..de6c6d1 100644
--- a/mandaye/backends/ldap_back.py
+++ b/mandaye/backends/ldap_back.py
@@ -145,3 +145,11 @@ class Association(object):
         mod_list = [(ldap.MOD_REPLACE, 'lastConnectionDate', last_connection)]
         storage_conn.modify_s(dn, mod_list)
 
+    @staticmethod
+    def has_sp_login(sp_login, sp_name):
+        results = storage_conn.search_s(config.ldap_base_dn, ldap.SCOPE_ONELEVEL,
+                filterstr='(&(objectClass=MandayeUser)(spName=%s)(spLogin=%s))' %\
+                        (sp_name, sp_login))
+        if results:
+            return True
+        return False
diff --git a/mandaye/backends/sql.py b/mandaye/backends/sql.py
index 31254f4..b2ef3d7 100644
--- a/mandaye/backends/sql.py
+++ b/mandaye/backends/sql.py
@@ -172,3 +172,15 @@ class Association(object):
         sp_user.last_connection = datetime.utcnow()
         storage_conn.add(sp_user)
 
+    @staticmethod
+    def has_sp_login(sp_login, sp_name):
+        sp_user = storage_conn.query(SPUser).\
+                join(ServiceProvider).\
+                filter(ServiceProvider.name==sp_name).\
+                filter(SPUser.login==sp_login).\
+                count()
+        if sp_user:
+            return True
+        return False
+
+