Combo box label selection

Hi,
I have 4 movie clips which act like buttons on a stage along with another movie clip and a combo box.Let’s call the button movie clips as 1_mc,2_mc,3_mc,4_mc. Let’s call the 5th movie clip as all_mc. This movie clip,“all_mc” has 4 keyframes inside of it,placed at a distance of 10s from each other.There is some content on each of these keyframes.I have labelled these keyframes as “1”,“2”,“3”,“4” respectively. Now when 1_mc,2_mc,3_mc,or 4_mc is clicked, the movie clip “all_mc” shows the content belonging to the appropriate movie clip released by showing the contents of the key frames labeled “1”,“2”,“3”,“4” respectively.
Now the combo box has labels “1”,“2”,“3”,“4”.With the data being “1”,“2”,“3”,“4” respectively,so that if item 3 is selected in the combo box, the contents belonging to the key frame labeled “3” are displayed in the movie “all_mc”.So in short,in this way,i have created a navigation wherein one could watch different content either by clicking the individual movie clips or by merely selecting a different label from the combo box.
The problem is that when ever i click the 1_mc,2_mc,3_mc,or 4_mc movieclips, the content of “all_mc” changes but the selected labels of the combo box does not change.For example,if i click on 3_mc,the contents of “all_mc” with keyframe labelled “3” is displayed but at the same time,i want the combo box to display “3” in the visible label rather than the default label,whcih is “1”.In short,i need a relationship between the movie clips 1_mc,2_mc,3_mc,4_mc and the combo box so that when 2_mc is clicked,the combobox label changes to 2, when 3_mc is clicked,the combobox label changes to 3,when 4_mc is clicked,the combobox label changes to 4,when 1_mc is clicked,the combobox label changes to 1.The default visible label which appears in the combo box when the movie loads is “1”.At the same time no matter what movie clip is clicked or no matter what label is selected in the combo box, the contents of “all_mc” belonging to that particular number are shown.
I would highly appreciate it if anyone could come up with a solution for this.I have tried to look up everywhere especially in Adobe help docs,but no use. Thanks in advance.