iArray=new Array(
	"http://www.yourit.nl/cltest/_images/random/1",
	"http://www.yourit.nl/cltest/_images/random/2",
	"http://www.yourit.nl/cltest/_images/random/3",
	"http://www.yourit.nl/cltest/_images/random/4",
	"http://www.yourit.nl/cltest/_images/random/5",
	"http://www.yourit.nl/cltest/_images/random/6",
	"http://www.yourit.nl/cltest/_images/random/7",
	"http://www.yourit.nl/cltest/_images/random/8",
	"http://www.yourit.nl/cltest/_images/random/9",
	"http://www.yourit.nl/cltest/_images/random/10",
	"http://www.yourit.nl/cltest/_images/random/11",
	"http://www.yourit.nl/cltest/_images/random/12",
	"http://www.yourit.nl/cltest/_images/random/13",
	"http://www.yourit.nl/cltest/_images/random/14",
	"http://www.yourit.nl/cltest/_images/random/15",
	"http://www.yourit.nl/cltest/_images/random/16",
	"http://www.yourit.nl/cltest/_images/random/17",
	"http://www.yourit.nl/cltest/_images/random/18",
	"http://www.yourit.nl/cltest/_images/random/19",
	"http://www.yourit.nl/cltest/_images/random/20",
	"http://www.yourit.nl/cltest/_images/random/21",
	"http://www.yourit.nl/cltest/_images/random/22",
	"http://www.yourit.nl/cltest/_images/random/23",
	"http://www.yourit.nl/cltest/_images/random/24",
	"http://www.yourit.nl/cltest/_images/random/25",
	"http://www.yourit.nl/cltest/_images/random/26",
	"http://www.yourit.nl/cltest/_images/random/27",
	"http://www.yourit.nl/cltest/_images/random/28",
	"http://www.yourit.nl/cltest/_images/random/29",
	"http://www.yourit.nl/cltest/_images/random/30",
	"http://www.yourit.nl/cltest/_images/random/31",
	"http://www.yourit.nl/cltest/_images/random/32",
	"http://www.yourit.nl/cltest/_images/random/33"
	);

  ri    = Math.floor(iArray.length*Math.random());
  ri    ='<img src="'+ iArray[ri]+ '.jpg" border="0" alt="">';


function subhook_emailCheck (emailStr) {
/* 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("Ongeldig e-mail adres.")
	return false
}
var user=matchArray[1]
var domain=matchArray[2]

// See if "user" is valid 
if (user.match(userPat)==null) {
    // user is not valid
    alert("Onbekende gebruiker")
    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 (var i=1;i<=4;i++) {
	    if (IPArray[i]>255) {
	        alert("Dit is een ip-adres. Ongeldig e-mail adres.")
		return false
	    }
    }
    return true
}

// Domain is symbolic name
var domainArray=domain.match(domainPat)
if (domainArray==null) {
	alert("Dit is een symbolische naam. Ongeldig e-mail adres.")
    return false
}

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

/* Now we need to break up the domain to get a count of how many atoms
   it consists of. */
var atomPat=new RegExp(atom,"g")
var domArr=domain.match(atomPat)
var len=domArr.length
if (domArr[domArr.length-1].length<2 || 
    domArr[domArr.length-1].length>3) {
   // the address must end in a two letter or three letter word.
   alert("Domein is ongeldig.")
   return false
}

// Make sure there's a host name preceding the domain.
if (len<2) {
   var errStr="Geen geldig e-mail adres."
   alert(errStr)
   return false
}

// If we've gotten this far, everything's valid!
return true;
}

function subh_checkForm(f)
{
if (!subhook_emailCheck(f.email.value)) {return false;}
}