Help with Regular Expressions

Hi

I need help in regular expressions:
I’m creating a Find and Replace tool for a text editor

the attached code is part of the code I use for Find Next Button, but it only finds [a-z] and [A-Z] and [0-9],
if the string contains any other character all code go wrong.
notice that the RegExp object is created dynamically so that it change from time to time.

any body can give me a code that find and string in the v_Find variable.

please see the code.

thanks a lot.
Attach Code

var matches:Array = new Array();
var StartIndexes:Array = new Array();
var i:Number;
var v_Find:String = new String();
var v_Modified:String = new String();
//====================
MyRegExp1 = new RegExp(v_Find, “gi”);
//====================
/*
inside Find Next button code I use:
(a lot of code but this is the part I need you to see)
/
//====================
v_Find = T1.text;
v_Modified = T3.text;
var MyRegExp1:RegExp;
i = 0;
while ((matches = MyRegExp1.exec(v_Modified)) != null) {
StartIndexes
= matches.index;
i++;
//trace(matches.index);
}