diff --git a/wp-includes/category-template.php b/wp-includes/category-template.php
index 7e112f53dd..a000988554 100644
--- a/wp-includes/category-template.php
+++ b/wp-includes/category-template.php
@@ -314,8 +314,9 @@ function category_description( $category = 0 ) {
  *     'echo' (bool|int) default is 1 - Whether to display or retrieve content.
  *     'depth' (int) - The max depth.
  *     'tab_index' (int) - Tab index for select element.
- *     'name' (string) - The name attribute value for selected element.
- *     'class' (string) - The class attribute value for selected element.
+ *     'name' (string) - The name attribute value for select element.
+ *     'id' (string) - The ID attribute value for select element. Defaults to name if omitted.
+ *     'class' (string) - The class attribute value for select element.
  *     'selected' (int) - Which category ID is selected.
  *
  * The 'hierarchical' argument, which is disabled by default, will override the
@@ -336,9 +337,10 @@ function wp_dropdown_categories( $args = '' ) {
 		'hide_empty' => 1, 'child_of' => 0,
 		'exclude' => '', 'echo' => 1,
 		'selected' => 0, 'hierarchical' => 0,
-		'name' => 'cat', 'class' => 'postform',
-		'depth' => 0, 'tab_index' => 0,
-		'taxonomy' => 'category', 'hide_if_empty' => false
+		'name' => 'cat', 'id' => '',
+		'class' => 'postform', 'depth' => 0,
+		'tab_index' => 0, 'taxonomy' => 'category',
+		'hide_if_empty' => false
 	);
 
 	$defaults['selected'] = ( is_category() ) ? get_query_var( 'cat' ) : 0;
@@ -357,11 +359,12 @@ function wp_dropdown_categories( $args = '' ) {
 		$tab_index_attribute = " tabindex=\"$tab_index\"";
 
 	$categories = get_terms( $taxonomy, $r );
-	$name = esc_attr($name);
-	$class = esc_attr($class);
+	$name = esc_attr( $name );
+	$class = esc_attr( $class );
+	$id = $id ? esc_attr( $id ) : $name;
 
 	if ( ! $r['hide_if_empty'] || ! empty($categories) )
-		$output = "<select name='$name' id='$name' class='$class' $tab_index_attribute>\n";
+		$output = "<select name='$name' id='$id' class='$class' $tab_index_attribute>\n";
 	else
 		$output = '';
 
diff --git a/wp-includes/user.php b/wp-includes/user.php
index f1d6ef24ef..5138eb034f 100644
--- a/wp-includes/user.php
+++ b/wp-includes/user.php
@@ -403,11 +403,12 @@ function setup_userdata($for_user_id = '') {
  * <li>order - Default is 'ASC'. Can also be 'DESC'.</li>
  * <li>include - User IDs to include.</li>
  * <li>exclude - User IDs to exclude.</li>
- * <li>multi - Default is 'false'. Whether to skip the ID attribute on the 'select' element.</li>
+ * <li>multi - Default is 'false'. Whether to skip the ID attribute on the 'select' element. A 'true' value is overridden when id argument is set.</li>
  * <li>show - Default is 'display_name'. User table column to display. If the selected item is empty then the user_login will be displayed in parentesis</li>
  * <li>echo - Default is '1'. Whether to display or retrieve content.</li>
  * <li>selected - Which User ID is selected.</li>
  * <li>name - Default is 'user'. Name attribute of select element.</li>
+ * <li>id - Default is the value of the 'name' parameter. ID attribute of select element.</li>
  * <li>class - Class attribute of select element.</li>
  * <li>blog_id - ID of blog (Multisite only). Defaults to ID of current blog.</li>
  * </ol>
@@ -426,6 +427,7 @@ function wp_dropdown_users( $args = '' ) {
 		'include' => '', 'exclude' => '', 'multi' => 0,
 		'show' => 'display_name', 'echo' => 1,
 		'selected' => 0, 'name' => 'user', 'class' => '', 'blog_id' => $GLOBALS['blog_id'],
+		'id' => '',
 	);
 
 	$defaults['selected'] = is_author() ? get_query_var( 'author' ) : 0;
@@ -459,9 +461,13 @@ function wp_dropdown_users( $args = '' ) {
 
 	$output = '';
 	if ( !empty($users) ) {
-		$id = $multi ? "" : "id='$name'";
+		$name = esc_attr( $name );
+		if ( $multi && ! $id )
+			$id = '';
+		else
+			$id = $id ? " id='" . esc_attr( $id ) . "'" : "id='$name'";
 
-		$output = "<select name='$name' $id class='$class'>\n";
+		$output = "<select name='{$name}'{$id} class='$class'>\n";
 
 		if ( $show_option_all )
 			$output .= "\t<option value='0'>$show_option_all</option>\n";