Why is this not working? "Dropdownbox disabling"

[c6ke]

Hi there!
I'm trying to use this code in order to disable the given dropdownbox. it disables but doesn't re-enable it again.
What is wrong?

<form name="MyForm" style="margin:0px">
<select name="doodoo" size="" class="selectdropdown">
<option>Option1</option>
<option>Option2</option>
<option>Option3</option>
</select>
</form>

<A style="COLOR: #000080; TEXT-DECORATION: none; CURSOR: pointer;" onClick="javascript:document.MyForm.doodoo.disable d='false'">Enabled</A>

<A style="COLOR: #000080; TEXT-DECORATION: none; CURSOR: pointer;" onClick="javascript:document.MyForm.doodoo.disable d='true'">Disabled</A>

[c6ke]

Got it:
<A style="COLOR: #000080; TEXT-DECORATION: none; CURSOR: pointer;" onClick="javascript:document.MyForm.doodoo.disable d=false">Enabled</A>

<A style="COLOR: #000080; TEXT-DECORATION: none; CURSOR: pointer;" onClick="javascript:document.MyForm.doodoo.disable d=true">Disabled</A>