diff --git a/preprocessor.cpp b/preprocessor.cpp
index fccd362a3..560a06a5f 100644
--- a/preprocessor.cpp
+++ b/preprocessor.cpp
@@ -173,6 +173,27 @@ std::string Preprocessor::removeSpaceNearNL( const std::string &str )
     return tmp;
 }
 
+std::string Preprocessor::replaceIfDefined( const std::string &str )
+{
+    std::string ret(str);
+    std::string::size_type pos = 0;
+    while ((pos = ret.find("#if defined(", pos)) != std::string::npos)
+    {
+        std::string::size_type pos2 = ret.find(")", pos+9);
+        if (pos2 > ret.length() - 1)
+            break;
+        if (ret[pos2+1] == '\n')
+        {
+            ret.erase( pos2, 1 );
+            ret.erase( pos + 3, 9 );
+            ret.insert( pos + 3, "def " );
+        }
+        ++pos;
+    }
+
+    return ret;
+}
+
 void Preprocessor::preprocess(std::istream &istr, std::string &processedFile, std::list<std::string> &resultConfigurations)
 {
     processedFile = read(istr);
@@ -198,6 +219,8 @@ void Preprocessor::preprocess(std::istream &istr, std::string &processedFile, st
             processedFile.insert( loc, "\n" );
     }
 
+    processedFile = replaceIfDefined(processedFile);
+
     // Get all possible configurations..
     resultConfigurations = getcfgs( processedFile );
 }
diff --git a/preprocessor.h b/preprocessor.h
index 6cf381414..be2cde3de 100644
--- a/preprocessor.h
+++ b/preprocessor.h
@@ -60,7 +60,9 @@ public:
      */
     static std::string getcode(const std::string &filedata, std::string cfg);
 
+#ifndef UNIT_TESTING
 private:
+#endif
 
     /**
      * Remove space that has new line character on left or right side of it.
@@ -70,6 +72,14 @@ private:
      */
     static std::string removeSpaceNearNL( const std::string &str );
 
+    /**
+     * Replace "#if defined" with "#ifdef" where possible
+     *
+     * @param str The string to be converted
+     * @return The replaced string
+     */
+    static std::string replaceIfDefined( const std::string &str );
+
     /**
      * Get all possible configurations. By looking at the ifdefs and ifndefs in filedata
      */
diff --git a/testpreprocessor.cpp b/testpreprocessor.cpp
index 2932f99bc..c512bbfa8 100644
--- a/testpreprocessor.cpp
+++ b/testpreprocessor.cpp
@@ -22,6 +22,7 @@
 
 
 #include "testsuite.h"
+#define UNIT_TESTING
 #include "preprocessor.h"
 
 #include <map>
@@ -61,6 +62,8 @@ private:
         TEST_CASE( if_cond1 );
 
         TEST_CASE( multiline );
+
+        TEST_CASE( if_defined );    // "#if defined(AAA)" => "#ifdef AAA"
     }
 
 
@@ -441,6 +444,20 @@ private:
         ASSERT_EQUALS( true, cmpmaps(actual, expected));
     }
 
+
+    void if_defined()
+    {
+        const char filedata[] = "#if defined(AAA)\n"
+                                "#endif\n";
+
+        // Expected result..
+        std::string expected( "#ifdef AAA\n#endif\n" );
+
+        // Compare result..
+        ASSERT_EQUALS( expected, Preprocessor::replaceIfDefined(filedata) );
+    }
+
+
 };
 
 REGISTER_TEST( TestPreprocessor )