diff --git a/codepot/src/codepot/libraries/converter.php b/codepot/src/codepot/libraries/converter.php
index a04eba31..308cacb1 100644
--- a/codepot/src/codepot/libraries/converter.php
+++ b/codepot/src/codepot/libraries/converter.php
@@ -67,56 +67,83 @@ class Converter
 	function HexToAscii($hex)
 	{
 		$ascii = '';
+		$is_hex = FALSE;
    
 		$len = strlen($hex);
-		if ($len > 0 && $hex[0] == '!')
-		{
-			for ($i = 1; $i < $len; $i++)
-			{
-				if ($hex[$i] == '!')
-				{
-					$j = $i + 1;
-					$k = $i + 2;
+		if ($len <= 0) return $ascii;
 
-					if ($k < $len && ctype_xdigit($hex[$j]) && ctype_xdigit($hex[$k]))
-					{
-						// !XY where X and Y are hexadeciman digits
-						$seg = chr(base_convert(substr($hex, $j, 2), 16, 10));
-						$i = $k;
-					}
-					else if ($j < $len)
-					{
-						// !X - X is taken as a character
-						$seg = $hex[$j];
-						$i = $j;
-					}
-					else
-					{
-						// the last charater is a backslash
-						$seg = $hex[$i];
-					}
-				}
-				else if ($hex[$i] == '|')
+
+		if ($hex[0] != '!')
+		{
+			$orglen = $len;
+			$is_hex = 1;
+			if ($len % 2 == 1) 
+			{
+				$hex = '0' . $hex;
+				$len++;
+			}
+   
+			for($i = 0; $i < $len; $i += 2)
+			{
+				if (!ctype_xdigit($hex[$i])  || !ctype_xdigit($hex[$i + 1]))
 				{
-					// colon to slash
-					$seg = '/';
+					$ascii = '';
+					$is_hex = FALSE;
+					break;		
 				}
-				else 
+				$ascii .= chr(base_convert(substr($hex, $i, 2), 16, 10));
+			}
+
+			if ($is_hex > 0) return $ascii;
+
+			# if the string not prefixed with '!' contains non-hexadecimal character,
+			# arrange it to treat it as if it's prefixed with '!'.
+			$startpos = $len - $orglen;
+		}
+		else 
+		{
+			$startpos = 1;
+		}
+
+	
+		for ($i = $startpos; $i < $len; $i++)
+		{
+			if ($hex[$i] == '!')
+			{
+				$j = $i + 1;
+				$k = $i + 2;
+
+				if ($k < $len && ctype_xdigit($hex[$j]) && ctype_xdigit($hex[$k]))
 				{
-					// normal character
+					// !XY where X and Y are hexadeciman digits
+					$seg = chr(base_convert(substr($hex, $j, 2), 16, 10));
+					$i = $k;
+				}
+				else if ($j < $len)
+				{
+					// !X - X is taken as a character
+					$seg = $hex[$j];
+					$i = $j;
+				}
+				else
+				{
+					// the last charater is a backslash
 					$seg = $hex[$i];
 				}
+			}
+			else if ($hex[$i] == '|')
+			{
+				// colon to slash
+				$seg = '/';
+			}
+			else 
+			{
+				// normal character
+				$seg = $hex[$i];
+			}
 
-				$ascii .= $seg;
-			}	
-		}
-		else
-		{
-			if (strlen($hex) % 2 == 1) $hex = '0' . $hex;
-   
-			for($i = 0; $i < strlen($hex); $i += 2)
-				$ascii .= chr(base_convert(substr($hex, $i, 2), 16, 10));
-		}
+			$ascii .= $seg;
+		}	
    
 		return $ascii;
 	}