stuck on visited state?

Can anyone help tell me why my CSS rollovers are showing the visited state after I have visited the page, but when I go back and rollover that link again it doesn't show the hover state and remains on the visited state. Surely the hover state should always be shown when the mouse is over the link?

Thanks

this is the css code

.SPEC:link { color: white ; font-size: 12px; font-weight: bold; line-height: 12px; text-decoration: none; }
.SPEC:visited { color: white ; font-size: 12px; line-height: 12px; text-decoration: none; }
.SPEC:hover { color: #e5e5e5 ; font-size: 12px; font-weight: bold; line-height: 12px; text-decoration: underline; }
.SPEC:active { color: #ff6c00 ; font-size: 12px; font-weight: bold; line-height: 12px; }