diff --git a/SoObjects/SOGo/SOGoDefaultsSource.h b/SoObjects/SOGo/SOGoDefaultsSource.h
index f2c0b9f95..47b0dad46 100644
--- a/SoObjects/SOGo/SOGoDefaultsSource.h
+++ b/SoObjects/SOGo/SOGoDefaultsSource.h
@@ -26,6 +26,8 @@
 #ifndef SOGODEFAULTSSOURCE_H
 #define SOGODEFAULTSSOURCE_H
 
+#import <Foundation/NSObject.h>
+
 @class NSArray;
 @class NSData;
 @class NSDictionary;
diff --git a/SoObjects/SOGo/SOGoLDAPDefaults.h b/SoObjects/SOGo/SOGoLDAPDefaults.h
index 1fe4db6ec..eaab81f4e 100644
--- a/SoObjects/SOGo/SOGoLDAPDefaults.h
+++ b/SoObjects/SOGo/SOGoLDAPDefaults.h
@@ -23,6 +23,8 @@
 #ifndef SOGOLDAPDEFAULTS_H
 #define SOGOLDAPDEFAULTS_H
 
+@class NSString;
+
 @protocol SOGoLDAPDefaults
 
 - (int) ldapQueryLimit;