I can't use the symbolic integration feature of Sage 4.8. I tested some simpler features that work fine, but whenever I try the integrate() function, I get

` ````
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "_sage_input_8.py", line 10, in <module>
exec compile(u'open("___code___.py","w").write("# -*- coding: utf-8 -*-\\n" + _support_.preparse_worksheet_cell(base64.b64decode("aW50ZWdyYXRlKHgseCk="),globals())+"\\n"); execfile(os.path.abspath("___code___.py"))
File "", line 1, in <module>
File "/tmp/tmprPuvfe/___code___.py", line 2, in <module>
exec compile(u'integrate(x,x)
File "", line 1, in <module>
File "/home/jacob/Sage/sage-4.7/local/lib/python2.6/site-packages/sage/misc/functional.py", line 716, in integral
return x.integral(*args, **kwds)
File "expression.pyx", line 8402, in sage.symbolic.expression.Expression.integral (sage/symbolic/expression.cpp:32273)
File "/home/jacob/Sage/sage-4.7/local/lib/python2.6/site-packages/sage/symbolic/integration/integral.py", line 614, in integrate
return indefinite_integral(expression, v)
File "function.pyx", line 418, in sage.symbolic.function.Function.__call__ (sage/symbolic/function.cpp:4623)
File "/home/jacob/Sage/sage-4.7/local/lib/python2.6/site-packages/sage/symbolic/integration/integral.py", line 84, in _eval_
res = integrator(f, x)
File "/home/jacob/Sage/sage-4.7/local/lib/python2.6/site-packages/sage/symbolic/integration/external.py", line 19, in maxima_integrator
result = maxima.sr_integral(expression,v)
File "lazy_import.pyx", line 167, in sage.misc.lazy_import.LazyImport.__getattr__ (sage/misc/lazy_import.c:1395)
File "lazy_import.pyx", line 110, in sage.misc.lazy_import.LazyImport._get_object (sage/misc/lazy_import.c:1047)
File "/home/jacob/Sage/sage-4.7/local/lib/python2.6/site-packages/sage/interfaces/maxima_lib.py", line 72, in <module>
from sage.libs.ecl import *
ImportError: libffi.so.4: cannot open shared object file: No such file or directory
```

I assume the problem occurred because I broke something when I upgraded from 4.7 to 4.8. However, I don't know how to make Sage reinstall its copy of libffi, or make it re-link its libraries, or whatever.

If Sage doesn't have its own libffi and is instead looking for the copy installed on my system, then I know the problem: my system doesn't have "libffi.so.4," it has "libffi.so.5." However, I don't know how to make sage look for libffi.so.5 instead of libffi.so.4, and I don't know what the significance of the number suffix is.

Thank you for your assistance.