This was reported by michael to sage-devel on Nov 27, 2007. It's a genuine
bug which gives incorrect mathematical results (hence the critical marking).
```
R=IntegerModRing(3^2)
A=PolynomialRing…
This is good:
```
sage: x = PolynomialRing(QQ,"x").gen()
sage: f = x^2-1
sage: factor(f)
(x - 1) * (x + 1)
```
This is bad:
```
sage: x = PolynomialRing(RR,"x").gen()
sage: f = x^2-1
sage: factor(…