diff --git a/trunk/research/st/common.h b/trunk/research/st/common.h
index 880b4f139..46868556f 100644
--- a/trunk/research/st/common.h
+++ b/trunk/research/st/common.h
@@ -144,9 +144,6 @@ typedef struct _st_stack {
     char *stk_bottom;           /* Lowest address of stack's usable portion */
     char *stk_top;              /* Highest address of stack's usable portion */
     void *sp;                   /* Stack pointer from C's point of view */
-    #ifdef __ia64__
-    void *bsp;                  /* Register stack backing store pointer */
-    #endif
 } _st_stack_t;
 
 
@@ -349,11 +346,7 @@ extern _st_eventsys_t *_st_eventsys;
     #define ST_UTIME_NO_TIMEOUT ((st_utime_t) -1LL)
 #endif
 
-#ifndef __ia64__
-    #define ST_DEFAULT_STACK_SIZE (64*1024)
-#else
-    #define ST_DEFAULT_STACK_SIZE (128*1024)  /* Includes register stack size */
-#endif
+#define ST_DEFAULT_STACK_SIZE (64*1024)
 
 #ifndef ST_KEYS_MAX
     #define ST_KEYS_MAX 16
diff --git a/trunk/research/st/sched.c b/trunk/research/st/sched.c
index faa66e38d..a66111a4c 100644
--- a/trunk/research/st/sched.c
+++ b/trunk/research/st/sched.c
@@ -532,9 +532,6 @@ _st_thread_t *st_thread_create(void *(*start)(void *arg), void *arg, int joinabl
     _st_stack_t *stack;
     void **ptds;
     char *sp;
-#ifdef __ia64__
-    char *bsp;
-#endif
     
     /* Adjust stack size */
     if (stk_size == 0) {
@@ -549,22 +546,6 @@ _st_thread_t *st_thread_create(void *(*start)(void *arg), void *arg, int joinabl
     /* Allocate thread object and per-thread data off the stack */
 #if defined (MD_STACK_GROWS_DOWN)
     sp = stack->stk_top;
-    #ifdef __ia64__
-    /*
-    * The stack segment is split in the middle. The upper half is used
-    * as backing store for the register stack which grows upward.
-    * The lower half is used for the traditional memory stack which
-    * grows downward. Both stacks start in the middle and grow outward
-    * from each other.
-    */
-    sp -= (stk_size >> 1);
-    bsp = sp;
-    /* Make register stack 64-byte aligned */
-    if ((unsigned long)bsp & 0x3f) {
-        bsp = bsp + (0x40 - ((unsigned long)bsp & 0x3f));
-    }
-    stack->bsp = bsp + _ST_STACK_PAD_SIZE;
-    #endif
     sp = sp - (ST_KEYS_MAX * sizeof(void *));
     ptds = (void **) sp;
     sp = sp - sizeof(_st_thread_t);
@@ -575,18 +556,6 @@ _st_thread_t *st_thread_create(void *(*start)(void *arg), void *arg, int joinabl
         sp = sp - ((unsigned long)sp & 0x3f);
     }
     stack->sp = sp - _ST_STACK_PAD_SIZE;
-#elif defined (MD_STACK_GROWS_UP)
-    sp = stack->stk_bottom;
-    thread = (_st_thread_t *) sp;
-    sp = sp + sizeof(_st_thread_t);
-    ptds = (void **) sp;
-    sp = sp + (ST_KEYS_MAX * sizeof(void *));
-    
-    /* Make stack 64-byte aligned */
-    if ((unsigned long)sp & 0x3f) {
-        sp = sp + (0x40 - ((unsigned long)sp & 0x3f));
-    }
-    stack->sp = sp + _ST_STACK_PAD_SIZE;
 #else
     #error Unknown OS
 #endif
@@ -600,11 +569,7 @@ _st_thread_t *st_thread_create(void *(*start)(void *arg), void *arg, int joinabl
     thread->start = start;
     thread->arg = arg;
     
-#ifndef __ia64__
     _ST_INIT_CONTEXT(thread, stack->sp, _st_thread_main);
-#else
-    _ST_INIT_CONTEXT(thread, stack->sp, stack->bsp, _st_thread_main);
-#endif
     
     /* If thread is joinable, allocate a termination condition variable */
     if (joinable) {
diff --git a/trunk/research/st/srs.c b/trunk/research/st/srs.c
index c65994089..017caee9a 100644
--- a/trunk/research/st/srs.c
+++ b/trunk/research/st/srs.c
@@ -11,10 +11,6 @@
 
 #include "public.h"
 
-#if defined(__ia64__)
-    #error "IA64 not supported"
-#endif
-
 #define srs_trace(msg, ...)   printf(msg, ##__VA_ARGS__);printf("\n")
 
 int io_port = 1990;