Converting an IIR filter from floating-point to fixed-point can be difficult, especially when the poles of the filter are close to the unit circle. The coefficients quantization error can make the filter unstable (as it is in this case). So it will not be possible to directly create a fixed-point filter with the same frequency preferences. However, depending on the application, one can use multirate/multistage FIR designs as they can be an efficient alternative to IIR designs for highly selective filters. FIR filters are much easier to convert to fixed-point.
Another alternative might be to use Wave Digital (also known as IIR polyphase) filters. A demo on this topic can be found by executing the following statement on the MATLAB command prompt (in R2008a):
web([matlabroot '/toolbox/filterdesign/filtdesdemos/html/iirallpassdemo.html'], '-helpbrowser')
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