function emailCheck( emailStr )
{

var strErrorMsg = "Adresa de E-Mail este invalida!";

/* The following variable tells the rest of the function whether or not
to verify that the address ends in a two-letter country or well-known
TLD. 1 means check it, 0 means don't. */

var checkTLD = 1;

/* The following is the list of known TLDs that an e-mail address must end with. */

var knownDomsPat = /^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum)$/;

/* The following pattern is used to check if the entered e-mail address
fits the user@domain format. It also is used to separate the username
from the domain. */

var emailPat = /^(.+)@(.+)$/;

/* The following string represents the pattern for matching all special
characters. We don't want to allow special characters in the address. 
These characters include ( ) < > @ , ; : \ " . [ ] */

var specialChars = "\\(\\)><@,;:\\\\\\\"\\.\\[\\]";

/* The following string represents the range of characters allowed in a 
username or domainname. It really states which chars aren't allowed.*/

var validChars = "\[^\\s" + specialChars + "\]";

/* The following pattern applies if the "user" is a quoted string (in
which case, there are no rules about which characters are allowed
and which aren't; anything goes). E.g. "jiminy cricket"@disney.com
is a legal e-mail address. */

var quotedUser = "(\"[^\"]*\")";

/* The following pattern applies for domains that are IP addresses,
rather than symbolic names. E.g. joe@[123.124.233.4] is a legal
e-mail address. NOTE: The square brackets are required. */

var ipDomainPat = /^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;

/* The following string represents an atom (basically a series of non-special characters.) */

var atom = validChars + '+';

/* The following string represents one word in the typical username.
For example, in john.doe@somewhere.com, john and doe are words.
Basically, a word is either an atom or quoted string. */

var word = "(" + atom + "|" + quotedUser + ")";

/* The following pattern describes the structure of the user. */

var userPat = new RegExp( "^" + word + "(\\." + word + ")*$" );

/* The following pattern describes the structure of a normal symbolic
domain, as opposed to ipDomainPat, shown above. */

var domainPat = new RegExp( "^" + atom + "(\\." + atom +")*$" );

/* Finally, let's start trying to figure out if the supplied address is valid. */

/* Begin with the coarse pattern to simply break up user@domain into
different pieces that are easy to analyze. */

var matchArray = emailStr.match( emailPat );

if ( matchArray == null ) {
	/* Too many/few @'s or something; basically, this address doesn't
	even fit the general mould of a valid e-mail address. */
	alert( strErrorMsg );
	return false;
}

var user = matchArray[ 1 ];
var domain = matchArray[ 2 ];

/* Start by checking that only basic ASCII characters are in the strings (0-127). */

for ( i = 0; i < user.length; i++ ) {
	if ( user.charCodeAt( i ) > 127 ) {
		alert( strErrorMsg );
		return false;
	}
}

for ( i = 0; i < domain.length; i++ ) {
	if ( domain.charCodeAt( i ) > 127 ) {
		alert( strErrorMsg );
		return false;
	}
}

/* See if "user" is valid. */

if ( user.match( userPat ) == null ) {
	/* user is not valid. */
	alert( strErrorMsg );
	return false;
}

/* If the e-mail address is at an IP address (as opposed to a symbolic
host name) make sure the IP address is valid. */

var IPArray = domain.match( ipDomainPat );

if ( IPArray != null ) {
	/* this is an IP address. */
	for ( i = 1; i <= 4; i++ ) {
		if ( IPArray[ i ] > 255 ) {
			alert( strErrorMsg );
			return false;
		}
	}
	return true;
}

/* Domain is symbolic name. Check if it's valid. */
 
var atomPat = new RegExp( "^" + atom + "$" );
var domArr = domain.split( "." );
var len = domArr.length;

for ( i = 0; i < len; i++ ) {
	if ( domArr[ i ].search( atomPat ) == -1 ) {
		alert( strErrorMsg );
		return false;
	}
}

/* Domain name seems valid, but now make sure that it ends in a
known top-level domain (like com, edu, gov) or a two-letter word,
representing country (uk, nl), and that there's a hostname preceding 
the domain or country. */

if ( checkTLD && domArr[ domArr.length - 1 ].length != 2 && domArr[ domArr.length - 1 ].search( knownDomsPat ) == -1 ) {
	alert( strErrorMsg );
	return false;
}

/* Make sure there's a host name preceding the domain. */

if ( len < 2 ) {
	alert( strErrorMsg );
	return false;
}

/* If we've gotten this far, everything's valid! */

return true;

}