diff --git a/app/models/user.rb b/app/models/user.rb
index 264cbd1..2614872 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -97,7 +97,7 @@ class User < Principal
 
   validates_presence_of :login, :firstname, :lastname, :mail, :if => Proc.new { |user| !user.is_a?(AnonymousUser) }
   validates_uniqueness_of :login, :if => Proc.new { |user| user.login_changed? && user.login.present? }, :case_sensitive => false
-  validates_uniqueness_of :mail, :if => Proc.new { |user| !user.mail.blank? }, :case_sensitive => false
+  validates_uniqueness_of :mail, :if => Proc.new { |user| user.mail_changed? && user.mail.present? }, :case_sensitive => false
   # Login must contain lettres, numbers, underscores only
   validates_format_of :login, :with => /^[a-z0-9_\-@\.]*$/i
   validates_length_of :login, :maximum => LOGIN_LENGTH_LIMIT