diff --git a/library/x509_crt.c b/library/x509_crt.c
index 6a127b2..6382c53 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -1273,11 +1273,15 @@
     {
         diff = n1[i] ^ n2[i];
 
-        if( ( n1[i] >= 'a' || n1[i] <= 'z' ) && ( diff == 0 || diff == 32 ) )
+        if( diff == 0 )
             continue;
 
-        if( ( n1[i] >= 'A' || n1[i] <= 'Z' ) && ( diff == 0 || diff == 32 ) )
+        if( diff == 32 &&
+            ( ( n1[i] >= 'a' && n1[i] <= 'z' ) ||
+              ( n1[i] >= 'A' && n1[i] <= 'Z' ) ) )
+        {
             continue;
+        }
 
         return( 1 );
     }