diff -up sage-5.10/spkg/build/sage-5.10/sage/libs/ecl.pxd.orig sage-5.10/spkg/build/sage-5.10/sage/libs/ecl.pxd
--- sage-5.10/spkg/build/sage-5.10/sage/libs/ecl.pxd.orig	2013-03-19 16:11:17.358705144 -0300
+++ sage-5.10/spkg/build/sage-5.10/sage/libs/ecl.pxd	2013-03-19 16:11:27.719705541 -0300
@@ -133,6 +133,7 @@ cdef extern from "ecl/ecl.h":
     cl_object ecl_read_from_cstring_safe(char *s, cl_object err)
     cl_object cl_write_to_string(cl_narg narg, cl_object o) 
     cl_object ecl_cstring_to_base_string_or_nil(char *s)
+    cl_object si_coerce_to_base_string(cl_object x)
     
     # S-expr evaluation and function calls
     
diff -up sage-5.10/spkg/build/sage-5.10/sage/libs/ecl.pyx.orig sage-5.10/spkg/build/sage-5.10/sage/libs/ecl.pyx
--- sage-5.10/spkg/build/sage-5.10/sage/libs/ecl.pyx.orig	2013-03-19 16:11:07.489704766 -0300
+++ sage-5.10/spkg/build/sage-5.10/sage/libs/ecl.pyx	2013-03-19 16:11:27.719705541 -0300
@@ -238,17 +238,19 @@ cdef cl_object ecl_safe_eval(cl_object f
         ...
         RuntimeError: ECL says: Console interrupt.
     """
+    cdef cl_object s
     ecl_sig_on()
     cl_funcall(2,safe_eval_clobj,form)
     ecl_sig_off()
 
     if ecl_nvalues > 1:
-        raise RuntimeError, "ECL says: "+ecl_base_string_pointer_safe(ecl_values(1))
+        s = si_coerce_to_base_string(ecl_values(1))
+        raise RuntimeError, "ECL says: "+ecl_base_string_pointer_safe(s)
     else:
         return ecl_values(0)
 
 cdef cl_object ecl_safe_funcall(cl_object func, cl_object arg) except NULL:
-    cdef cl_object l
+    cdef cl_object l, s
     l = cl_cons(func,cl_cons(arg,Cnil));
 
     ecl_sig_on()
@@ -256,17 +258,20 @@ cdef cl_object ecl_safe_funcall(cl_objec
     ecl_sig_off()
 
     if ecl_nvalues > 1:
-        raise RuntimeError, "ECL says: "+ecl_base_string_pointer_safe(ecl_values(1))
+        s = si_coerce_to_base_string(ecl_values(1))
+        raise RuntimeError, "ECL says: "+ecl_base_string_pointer_safe(s)
     else:
         return ecl_values(0)
 
 cdef cl_object ecl_safe_apply(cl_object func, cl_object args) except NULL:
+    cdef cl_object s
     ecl_sig_on()
     cl_funcall(3,safe_apply_clobj,func,args)
     ecl_sig_off()
 
     if ecl_nvalues > 1:
-        raise RuntimeError, "ECL says: "+ecl_base_string_pointer_safe(ecl_values(1))
+        s = si_coerce_to_base_string(ecl_values(1))
+        raise RuntimeError, "ECL says: "+ecl_base_string_pointer_safe(s)
     else:
         return ecl_values(0)
 
@@ -316,10 +321,11 @@ def print_objects():
         HELLO
     """
     
-    cdef cl_object c
+    cdef cl_object c, s
     c = list_of_objects
     while True:
-        print ecl_base_string_pointer_safe(cl_write_to_string(1,cl_car(c)))
+        s = si_coerce_to_base_string(cl_write_to_string(1,cl_car(c)))
+        print ecl_base_string_pointer_safe(s)
         c=cl_cadr(c)
         if c == Cnil:
             break
@@ -394,6 +400,7 @@ cdef cl_object python_to_ecl(pyobj) exce
         raise TypeError,"Unimplemented type for python_to_ecl"
 
 cdef ecl_to_python(cl_object o):
+    cdef cl_object s
     cdef Integer N
     # conversions from an ecl object to a python object.
 
@@ -428,7 +435,8 @@ cdef ecl_to_python(cl_object o):
                 return tuple(L)
         return L
     else:
-        return ecl_base_string_pointer_safe(cl_write_to_string(1,o))
+        s = si_coerce_to_base_string(cl_write_to_string(1,o))
+        return ecl_base_string_pointer_safe(s)
 
 #Maxima's BFLOAT multiprecision float type can be read with:
 #def bfloat_to_python(e):
@@ -644,7 +652,7 @@ cdef class EclObject:
 
         """
         cdef cl_object s
-        s = cl_write_to_string(1,self.obj)
+        s = si_coerce_to_base_string(cl_write_to_string(1,self.obj))
         return ecl_base_string_pointer_safe(s)
 
     def __hash__(self):