java - ArrayList.add throws ArrayIndexOutOfBoundsException

I am trying to add a object to a ArrayList and its throwing ArrayIndexOutOfBoundsException
Following is the code

private void populateInboxResultHolder(List inboxErrors){
    inboxList = new ArrayList();
    try{                
        inboxHolder = new InboxResultHolder();
        //Lots of Code
        inboxList.add(inboxHolder);

    }catch(Exception e){
        e.printStackTrace();
    }
}

And the exception is

[3/7/12 15:41:26:715 UTC] 00000045 SystemErr     R java.lang.ArrayIndexOutOfBoundsException
[3/7/12 15:41:26:721 UTC] 00000045 SystemErr     R      at java.util.ArrayList.add(ArrayList.java:378)

[3/7/12 15:41:26:721 UTC] 00000045 SystemErr     R      at com.ml.fusion.ui.common.web.bean.inbox.InboxSearchBean.populateInboxResultHolder(InboxSearchBean.java:388)    
[3/7/12 15:41:26:721 UTC] 00000045 SystemErr     R      at com.ml.fusion.ui.common.web.bean.inbox.InboxSearchBean.searchInboxErrors(InboxSearchBean.java:197)
[3/7/12 15:41:26:721 UTC] 00000045 SystemErr     R      at com.ml.fusion.ui.common.web.bean.inbox.InboxSearchBean.viewInbox(InboxSearchBean.java:207)

But according to the signature of ArrayList.add it should not throw this exception.
Please help.