diff --git a/mtx-1.3.12/mtxl.c b/mtx-1.3.12/mtxl.c
index 8a9e34b..a8dbceb 100644
--- a/mtx-1.3.12/mtxl.c
+++ b/mtx-1.3.12/mtxl.c
@@ -632,12 +632,10 @@ void copy_char_buffer(unsigned char *src, unsigned char *dest, int num)
   for (i=0; i < num; i++)
  {
    if (isalnum(*src)) {
-       *dest = *src;
+       *dest++ = *src;
    }
    src++;
-   dest++;
  }
- *dest = 0; 
 }
 
 /* This #%!@# routine has more parameters than I can count! */