diff --git a/CheckOther.cpp b/CheckOther.cpp
index a0ff05b7c..29e946c14 100644
--- a/CheckOther.cpp
+++ b/CheckOther.cpp
@@ -59,6 +59,39 @@ void WarningIsDigit()
 //---------------------------------------------------------------------------
 
 
+
+//---------------------------------------------------------------------------
+// Use standard function "isalpha" instead
+//---------------------------------------------------------------------------
+
+void WarningIsAlpha()
+{
+    for (TOKEN *tok = tokens; tok; tok = tok->next)
+    {
+        bool err = false;
+
+        if ( tok->str[0] != '(' )
+            continue;
+
+        err |= match(tok, "( var >= 'A' && var <= 'Z' ) || ( var >= 'a' && var <= 'z' )");
+        err |= match(tok, "( var >= 'a' && var <= 'z' ) || ( var >= 'A' && var <= 'Z' )");
+        err |= match(tok, "( * var >= 'A' && * var <= 'Z' ) || ( * var >= 'a' && * var <= 'z' )");
+        err |= match(tok, "( * var >= 'a' && * var <= 'z' ) || ( * var >= 'A' && * var <= 'Z' )");
+        err |= match(tok, "( ( var >= 'A' ) && ( var <= 'Z' ) ) || ( ( var >= 'a' ) && ( var <= 'z' ) )");
+        err |= match(tok, "( ( var >= 'a' ) && ( var <= 'z' ) ) || ( ( var >= 'A' ) && ( var <= 'Z' ) )");
+        err |= match(tok, "( ( * var >= 'A' ) && ( * var <= 'Z' ) ) || ( ( * var >= 'a' ) && ( * var <= 'z' ) )");
+        err |= match(tok, "( ( * var >= 'a' ) && ( * var <= 'z' ) ) || ( ( * var >= 'A' ) && ( * var <= 'Z' ) )");
+        if (err)
+        {
+            std::ostringstream ostr;
+            ostr << FileLine(tok) << ": The condition can be simplified; use 'isalpha'";
+            ReportErr(ostr.str());
+        }
+    }
+}
+//---------------------------------------------------------------------------
+
+
 //---------------------------------------------------------------------------
 // Redundant code..
 //---------------------------------------------------------------------------
diff --git a/CheckOther.h b/CheckOther.h
index e4397452f..aaf0a9941 100644
--- a/CheckOther.h
+++ b/CheckOther.h
@@ -10,6 +10,9 @@ void WarningOldStylePointerCast();
 // Use standard functions instead
 void WarningIsDigit();
 
+// Use standard functions instead
+void WarningIsAlpha();
+
 // Redundant code
 void WarningRedundantCode();
 
diff --git a/main.cpp b/main.cpp
index 888d6e413..08ca67052 100644
--- a/main.cpp
+++ b/main.cpp
@@ -74,6 +74,7 @@ static void CppCheck(const char FileName[])
     if ( ShowWarnings )
     {
         // Including header which is not needed
+        // Todo: This is really slow!
         WarningIncludeHeader();
     }
 
@@ -110,6 +111,7 @@ static void CppCheck(const char FileName[])
 
         // Use standard functions instead
         WarningIsDigit();
+        WarningIsAlpha();
 
         CheckOperatorEq1();