Adjustments for compatibility with the currrent (Tcl 8.4.0+) channel
implementation.

diff --git a/exp_chan.c b/exp_chan.c
index c92e26b6fbd02305..944200a63b102672 100644
--- a/exp_chan.c
+++ b/exp_chan.c
@@ -60,7 +60,7 @@ void			exp_background_channelhandler _ANSI_ARGS_((ClientData,
 
 Tcl_ChannelType expChannelType = {
     "exp",				/* Type name. */
-    ExpBlockModeProc,			/* Set blocking/nonblocking mode.*/
+    TCL_CHANNEL_VERSION_2,
     ExpCloseProc,			/* Close proc. */
     ExpInputProc,			/* Input proc. */
     ExpOutputProc,			/* Output proc. */
@@ -70,6 +70,7 @@ Tcl_ChannelType expChannelType = {
     ExpWatchProc,			/* Initialize notifier. */
     ExpGetHandleProc,			/* Get OS handles out of channel. */
     NULL,				/* Close2 proc */
+    ExpBlockModeProc,			/* Set blocking/nonblocking mode.*/
 };
 
 typedef struct ThreadSpecificData {