diff --git a/src/TabComplete.js b/src/TabComplete.js
index 5a6bfa8343..c49ef19e7f 100644
--- a/src/TabComplete.js
+++ b/src/TabComplete.js
@@ -45,6 +45,10 @@ class TabComplete {
         this.textArea = textArea;
     }
 
+    isTabCompleting() {
+        return this.tabStruct.completing;
+    }
+
     next() {
         this.tabStruct.index++;
         this.setCompletionOption();
@@ -117,15 +121,27 @@ class TabComplete {
         }
     }
 
+    /**
+     * @param {DOMEvent} e
+     * @return {Boolean} True if the tab complete state changed as a result of
+     * this event.
+     */
     onKeyDown(ev) {
         if (ev.keyCode !== KEY_TAB) {
             if (ev.keyCode !== KEY_SHIFT && this.tabStruct.completing) {
                 // they're resuming typing; reset tab complete state vars.
                 this.tabStruct.completing = false;
                 this.tabStruct.index = 0;
+                return true;
             }
             return false;
         }
+
+        if (!this.textArea) {
+            console.error("onKeyDown called before a <textarea> was set!");
+            return false;
+        }
+
         // init struct if necessary
         if (!this.tabStruct.completing) {
             this.tabStruct.completing = true;
diff --git a/src/components/structures/RoomView.js b/src/components/structures/RoomView.js
index e7b97021df..853eda65a7 100644
--- a/src/components/structures/RoomView.js
+++ b/src/components/structures/RoomView.js
@@ -34,6 +34,7 @@ var WhoIsTyping = require("../../WhoIsTyping");
 var Modal = require("../../Modal");
 var sdk = require('../../index');
 var CallHandler = require('../../CallHandler');
+var TabComplete = require("../../TabComplete");
 var Resend = require("../../Resend");
 var dis = require("../../dispatcher");
 
@@ -85,6 +86,12 @@ module.exports = React.createClass({
         MatrixClientPeg.get().on("RoomState.members", this.onRoomStateMember);
         MatrixClientPeg.get().on("sync", this.onSyncStateChange);
         this.savedScrollState = {atBottom: true};
+        // xchat-style tab complete, add a colon if tab
+        // completing at the start of the text
+        this.tabComplete = new TabComplete({
+            startingWordSuffix: ": ",
+            wordSuffix: " "
+        });
     },
 
     componentWillUnmount: function() {
@@ -1357,7 +1364,9 @@ module.exports = React.createClass({
             );
             if (canSpeak) {
                 messageComposer =
-                    <MessageComposer room={this.state.room} roomView={this} uploadFile={this.uploadFile} callState={this.state.callState} />
+                    <MessageComposer
+                        room={this.state.room} roomView={this} uploadFile={this.uploadFile}
+                        callState={this.state.callState} tabComplete={this.tabComplete} />
             }
 
             // TODO: Why aren't we storing the term/scope/count in this format
diff --git a/src/components/views/rooms/MessageComposer.js b/src/components/views/rooms/MessageComposer.js
index 3978ef2154..f4a694a123 100644
--- a/src/components/views/rooms/MessageComposer.js
+++ b/src/components/views/rooms/MessageComposer.js
@@ -31,7 +31,6 @@ var MatrixClientPeg = require("../../../MatrixClientPeg");
 var SlashCommands = require("../../../SlashCommands");
 var Modal = require("../../../Modal");
 var CallHandler = require('../../../CallHandler');
-var TabComplete = require("../../../TabComplete");
 var sdk = require('../../../index');
 
 var dis = require("../../../dispatcher");
@@ -65,6 +64,10 @@ function mdownToHtml(mdown) {
 module.exports = React.createClass({
     displayName: 'MessageComposer',
 
+    propTypes: {
+        tabComplete: React.PropTypes.any
+    },
+
     componentWillMount: function() {
         this.oldScrollHeight = 0;
         this.markdownEnabled = MARKDOWN_ENABLED;
@@ -168,14 +171,9 @@ module.exports = React.createClass({
             this.props.room.roomId
         );
         this.resizeInput();
-
-        // xchat-style tab complete, add a colon if tab
-        // completing at the start of the text
-        this._tabComplete = new TabComplete({
-            textArea: this.refs.textarea,
-            startingWordSuffix: ": ",
-            wordSuffix: " "
-        });
+        if (this.props.tabComplete) {
+            this.props.tabComplete.setTextArea(this.refs.textarea);
+        }
     },
 
     componentWillUnmount: function() {
@@ -233,7 +231,9 @@ module.exports = React.createClass({
                     return m.name || m.userId;
                 });
             }
-            this._tabComplete.setCompletionList(memberList);
+            if (this.props.tabComplete) {
+                this.props.tabComplete.setCompletionList(memberList);
+            }
         }
         else if (ev.keyCode === KeyCode.UP) {
             var input = this.refs.textarea.value;
@@ -253,7 +253,10 @@ module.exports = React.createClass({
                 this.resizeInput();
             }
         }
-        this._tabComplete.onKeyDown(ev);
+
+        if (this.props.tabComplete) {
+            this.props.tabComplete.onKeyDown(ev);
+        }
 
         var self = this;
         setTimeout(function() {