A bug in Apple's Macintosh OS X may cause display and printing problems using PostScript versions of the MathType symbolic (non-alphabetic) fonts. Other symbolic fonts (e.g. PostScript versions of Symbol) may also be affected. The specific problem is that certain characters are not drawn correctly.

By default, MathType uses TrueType versions of the MathType fonts. You will not experience this problem if you use the TrueType fonts. Users who have installed the PostScript fonts and disabled the TrueType versions may experience this issue.

Reason

The MathType 6.7 Installer places copies of MathType's TrueType fonts in your Fonts folder. While most applications now prefer TrueType or OpenType fonts, some users may still need to work with older PostScript Type 1 fonts. While MacOS still supports PostScript fonts to a certain extent, beginning with version 10.5 there are serious issues with certain kinds of PostScript Type 1 fonts that prevent them from working with MathType. These issues are described below.

However, since MathType Mac 6.7 also supports MacOS 10.4.9, where PostScript fonts can be used with MathType, we have provided PostScript versions of the Euclid and MT Extra fonts. These fonts are in LWFN ("LaserWriter font") format, meaning they consist of suitcases containing bitmap fonts plus a collection of Type 1 outline fonts. If you wish to install MathType's PostScript fonts, you can read about how to do that in the "About the PostScript Fonts" found under the MathType application folder.

There are three known problems with PostScript fonts on MacOS X that affect MathType:

1) Under MacOS 10.5 and later, PostScript fonts cannot be used with the deprecated PICT image format. Since Microsoft Office and Apple iWork '09 both use PICT images internally to display MathType equations, this means that you cannot use PostScript fonts with MathType in these applications.

2) MacOS X draws the wrong glyphs for many characters in Euclid Symbol and MT Extra/Euclid Extra.

Under 10.4.9, the issue affected eight characters in Euclid Symbol and six in MT Extra/Euclid Extra (listed below). This problem will also affect other symbolic PostScript fonts you may have and is due to a bug with how MacOS X handles symbolic fonts. The bug affects screen and printed output on MacOS X, but not EPS output. We have notified Apple about this issue, and any concerns should be raised directly with Apple.

Euclid Symbol:

infinity (replaced by bullet)
proportional to (replaced by mu)
not equal to (replaced by pi)
identical to (replaced by integral)
weierstrass 'p' (replaced by radical)
circled plus (replaced by approximately equal to)
superset of (replaced by ellipsis)
logical or (replaced by slash)

Euclid Extra/MT Extra:

integral loop (replaced by bullet)
unknown glyph (replaced by space)
'fi' ligature (replaced by apple)
dotless i (replaced by superscript 3)
fraction slash (replaced by caron)
double acute accent (replaced by degree)

Under 10.5 and later, the problem is much worse and most characters are affected, making the MathType fonts effectively unusable.

3) If you assign a symbolic PostScript font (e.g., Euclid Symbol) to the "Symbol" style in MathType's Define Styles dialog, some fence templates (parentheses, braces) draw over-stretched on screen but will print at the right size.

Demonstrating the problem without involving MathType or its fonts

This problem can also be reproduced without using MathType or its fonts, thereby indicating that the underlying problem is not caused by MathType. If you are an engineer or support person without MathType interested in reproducing the problem, or you are just curious to see it outside of MathType, perform the following steps, which were tested with Mac OS X 10.3.4 and Microsoft Office X.

Install a PostScript version of the Symbol font and disable or remove the TrueType version (Adobe distributes a PostScript Symbol font).
Launch Word X.
Go to Insert | Symbol and select the Symbol font. In the corresponding character map, search for the ∞ (Infinity) symbol. You will likely not find this symbol (due to the bug), so find it at character position 165, Unicode character 61605. Select it and click Insert.
Notice in the Word document that the 'Infinity' symbol has been substituted by an incorrect character, possibly the degree symbol or bullet.
Print the Word document and see that the same character(s) print incorrectly as well.

Solution

There is no real solution to this problem until the bug is fixed by Apple. A workaround, when it affects MathType, is to use the TrueType versions of the MathType fonts. These fonts are installed by default, so if you have replaced these with the PostScript versions, just replace the TrueType versions back again. An easier way to manage fonts in OS X 10.3 and later is to use FontBook to disable the MathType-related PostScript fonts when using MathType and enable the TrueType versions.

Getting This Problem Addressed by Apple

While we have reported this bug to Apple (bug #3574571), we encourage all users to report it to them as well so that Apple can appreciate the need to devote additional programming resources to it. It is important that their customers continue to report their own experience so that Apple understands how widespread this problem is. Most often, reports from actual users have a greater impact on bugs getting addressed than those submitted by independent software vendors such as us. Design Science is committed to working with Apple to help resolve this problem.

You can report this problem and any other problems you have with the Macintosh OS at http://www.apple.com/support/.
To report and track bugs via the Apple Developer Connection, visit http://developer.apple.com/bugreporter/index.html.

If you can contact their Technical Support Staff by telephone your report will likely carry even more weight. You can contact Apple Technical Support at (800) 275-2273.