Index: source/blender/src/transform.c
===================================================================
--- source/blender/src/transform.c	(revision 15367)
+++ source/blender/src/transform.c	(working copy)
@@ -843,7 +843,12 @@
 			break;
 		case ZKEY:
 			if ((Trans.flag & T_NO_CONSTRAINT)==0) {
-				if (cmode == 'Z') {
+				if (cmode == 'Y') {
+					if (Trans.flag & T_2D_EDIT) {
+						stopConstraint(&Trans);
+					}
+				}
+				else if (cmode == 'Z') {
 					if (Trans.con.mode & CON_USER) {
 						stopConstraint(&Trans);
 					}
@@ -854,7 +859,11 @@
 							setUserConstraint(&Trans, (CON_AXIS0|CON_AXIS1), "locking %s Z");
 					}
 				}
-				else if ((Trans.flag & T_2D_EDIT)==0) {
+				else if (Trans.flag & T_2D_EDIT) {
+					/* Treat Z as Y in 2D case */
+					setConstraint(&Trans, mati, (CON_AXIS1), "along Y axis");
+				}
+				else {
 					if (G.qual == 0)
 						setConstraint(&Trans, mati, (CON_AXIS2), "along global Z");
 					else if (G.qual == LR_SHIFTKEY)
Index: source/blender/src/editseq.c
===================================================================
--- source/blender/src/editseq.c	(revision 15367)
+++ source/blender/src/editseq.c	(working copy)
@@ -3475,6 +3475,7 @@
 					}
 					break;
 				case YKEY:
+				case ZKEY:
 					if(!(midtog && (proj == 1))) {
 						midtog= ~midtog;
 					}