[TYPO3]Problem with GMENU

[Reena]

Hi All,

I want to implement drop down horizontal menu in my site. My code is here:

page.includeLibs.gmenu_layers = media/scripts/gmenu_layers.php
temp.topnavi = HMENU
temp.topnavi.1 = GMENU_LAYERS
temp.topnavi.1 {
layerStyle = 
position:absolute;left:0px;top:30px;width:10px;VISIBILITY:hidden;
xPosOffset =-10
lockPosition = x
expAll=1
NO {
backColor = #cccccc
XY = [10.w]+10, 14
10 = TEXT
10.text.field = title
10.offset = 5,10
}
}
temp.topnavi.2 = GMENU
page.10.2.wrap = |<BR>
page.10.2.NO {
backColor = #99cccc
XY = 120, 14
10 = TEXT
10.text.field = title
10.offset = 5,10
}

But getting following error: Fatal error: Call to undefined function: 
imagegif() in D:\project\srijan\t3lib\class.t3lib_stdgraphic.php on line 
2594

Could anybody help me out in solving this problem.

Thank You,

Warm Regards,
Reena Chandel