Clear t:alerts messages

Hi,
I use alertManager.success to output t:alerts messages after the use press
the Save button. If the user press the Save button multiple times, I would
get multiple t:alerts messages displayed. How do I clear the previous
t:alerts messages so that only 1 message is displayed?

Here is my tml file

<div class="center">

<t:alerts/>

*</div>*

<t:zone t:id="detailZone" id="detailZone" >

<t:core.usermgmt.UserDetailComp t:id="detail" mode="actionMode"
previewUser="selectedUser" function="showFunctions"/>

*</t:zone>*

**
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Any help would be appreciated. Thanks.
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