Index: moodle/mod/assignment/lang/en/assignment.php
--- moodle/mod/assignment/lang/en/assignment.php Base (1.9)
+++ moodle/mod/assignment/lang/en/assignment.php Locally Modified (Based On 1.9)
@@ -72,6 +72,7 @@
 $string['duedateno'] = 'No due date';
 $string['early'] = '{$a} early';
 $string['editmysubmission'] = 'Edit my submission';
+$string['addsubmission'] = 'Add submission';
 $string['emailstudents'] = 'Email alerts to students';
 $string['emailteachermail'] = '{$a->username} has updated their assignment submission
 for \'{$a->assignment}\'


Index: moodle/mod/assignment/type/online/assignment.class.php
--- moodle/mod/assignment/type/online/assignment.class.php Base (1.91)
+++ moodle/mod/assignment/type/online/assignment.class.php Locally Modified (Based On 1.91)
@@ -125,8 +126,13 @@
             }
             echo $OUTPUT->box_end();
             if (!$editmode && $editable) {
+                if (!empty($submission)) {
+                    $submitbutton = "editmysubmission";
+                } else {
+                    $submitbutton = "addsubmission";
+                }
                 echo "<div style='text-align:center'>";
-                echo $OUTPUT->single_button(new moodle_url('view.php', array('id'=>$this->cm->id, 'edit'=>'1')), get_string('editmysubmission', 'assignment'));
+                echo $OUTPUT->single_button(new moodle_url('view.php', array('id'=>$this->cm->id, 'edit'=>'1')), get_string($submitbutton, 'assignment'));
                 echo "</div>";
             }