Occasionally I get lots of error messages on constant expressions in
case statements.

./wr/doc/tags/IMG.java:86: Constant expression required.
          case ALIGN_TOP:
          ^
./wr/doc/tags/IMG.java:88: Constant expression required.
          case ALIGN_TEXTTOP:
          ^
./wr/doc/tags/IMG.java:90: Constant expression required.
          case ALIGN_MIDDLE:
          ^
./wr/doc/tags/IMG.java:92: Constant expression required.
          case ALIGN_ABSMIDDLE:
          ^
./wr/doc/tags/IMG.java:94: Constant expression required.
          case ALIGN_BASELINE:
          ^
./wr/doc/tags/IMG.java:95: Constant expression required.
          case ALIGN_BOTTOM:
          ^
./wr/doc/tags/IMG.java:97: Constant expression required.
          case ALIGN_ABSBOTTOM:
          ^
./wr/doc/tags/IMG.java:106: Constant expression required.
          case ALIGN_TOP:
          ^
./wr/doc/tags/IMG.java:108: Constant expression required.
          case ALIGN_TEXTTOP:
          ^
./wr/doc/tags/IMG.java:110: Constant expression required.
          case ALIGN_MIDDLE:
          ^
./wr/doc/tags/IMG.java:112: Constant expression required.
          case ALIGN_ABSMIDDLE:
          ^
./wr/doc/tags/IMG.java:114: Constant expression required.
          case ALIGN_BASELINE:
          ^
./wr/doc/tags/IMG.java:115: Constant expression required.
          case ALIGN_BOTTOM: