The datasheet is a little confusing. If I'm reading this right, on page 1, C1 isn't necessarily required. Then, Figure 11 on page 10 shows the typical application for a fixed output regulator (which this is), and there are no capacitors. Perhaps they were just omitting them under the assumption that it was understood that they are needed? Anyone know?
http://www.ti.com/lit/ds/symlink/lm1085.pdf
http://www.ti.com/lit/ds/symlink/lm1085.pdf