<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>breadbox</author><text>And as others have noted, this doesn&amp;#x27;t make sense given that passwords are case-sensitive and are required to include uppercase characters.&lt;p&gt;If there&amp;#x27;s a mechanism for specifying case on the phone, there can be a mechanism for specifying Q and Z unambiguously. I certainly have used VM systems that explicitly told me to &amp;quot;use 7 to represent Q and 9 to represent Z.&amp;quot;&lt;p&gt;A contractual requirement is one possibility that could explain it, but my suspicion is rather that some legacy code in the system uses Q and Z as special escape characters or delimiters (because of their absence on the phone dial), and it&amp;#x27;s not worth the cost to try to fix the ancient code (or do all the testing necessary to be confident of deploying a workaround).</text><parent_chain><item><author>dredmorbius</author><text>As several people have noted, the Q&amp;#x2F;Z restriction likely arises from inputting passwords from a telephone keypad.&lt;p&gt;What I haven&amp;#x27;t seen is a statement as to why this would have been a problem.  The reason is that Q and Z were mapped &lt;i&gt;inconsistently&lt;/i&gt; across various phone keypads.  The present convention of PQRS on 7 and WXYZ on 9 wasn&amp;#x27;t settled on until fairly late in the game, and as noted, the airline reservation system, SABRE, is one of the oldest widely-used public-facing computer systems still in existence, dating to the 1950s.&lt;p&gt;&lt;a href=&quot;https://en.wikipedia.org/wiki/Sabre_(computer_system)&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Sabre_(computer_system)&lt;/a&gt;&lt;p&gt;The 7&amp;#x2F;9 standard, by the way comes from the international standard ITU E 1.161, also known as ANSI T1.703-1995&amp;#x2F;1999 and ISO&amp;#x2F;IEC 9995-8:1994).&lt;p&gt;&lt;a href=&quot;http://www.dialabc.com/words/history.html&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;www.dialabc.com&amp;#x2F;words&amp;#x2F;history.html&lt;/a&gt;&lt;p&gt;Other keypads may not assign Q or Z at all, or assign it to various other numbers, 1 for Australian Classic, 0 for UK Classic and Mobile 1.&lt;p&gt;&lt;a href=&quot;http://www.dialabc.com/motion/keypads.html&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;www.dialabc.com&amp;#x2F;motion&amp;#x2F;keypads.html&lt;/a&gt;&lt;p&gt;Similarly, special characters can be entered via numerous mechanisms on phone keyboards.&lt;p&gt;My suspicion is that there&amp;#x27;s a contractual requirement somewhere to retain compatibility with an existing infrastructure somewhere.</text></item></parent_chain></comment><story><title>Passwords for JetBlue accounts cannot contain a Q or a Z</title><url>http://help.jetblue.com/SRVS/CGI-BIN/webisapi.dll?New,Kb=askBlue,case=obj(403864)</url></story>
<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>gcb0</author><text>so, they have a requirement to maintain compatibility with telephone password input, but require an uppercase character as well? it does not make any sense.&lt;p&gt;this is incompetent developers in a dysfunctional environment. there is no good light anyone can throw at it. and no, having the system live since the 50s is not a good excuse. it is certainly not the same system, for obvious reason.</text><parent_chain><item><author>dredmorbius</author><text>As several people have noted, the Q&amp;#x2F;Z restriction likely arises from inputting passwords from a telephone keypad.&lt;p&gt;What I haven&amp;#x27;t seen is a statement as to why this would have been a problem.  The reason is that Q and Z were mapped &lt;i&gt;inconsistently&lt;/i&gt; across various phone keypads.  The present convention of PQRS on 7 and WXYZ on 9 wasn&amp;#x27;t settled on until fairly late in the game, and as noted, the airline reservation system, SABRE, is one of the oldest widely-used public-facing computer systems still in existence, dating to the 1950s.&lt;p&gt;&lt;a href=&quot;https://en.wikipedia.org/wiki/Sabre_(computer_system)&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Sabre_(computer_system)&lt;/a&gt;&lt;p&gt;The 7&amp;#x2F;9 standard, by the way comes from the international standard ITU E 1.161, also known as ANSI T1.703-1995&amp;#x2F;1999 and ISO&amp;#x2F;IEC 9995-8:1994).&lt;p&gt;&lt;a href=&quot;http://www.dialabc.com/words/history.html&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;www.dialabc.com&amp;#x2F;words&amp;#x2F;history.html&lt;/a&gt;&lt;p&gt;Other keypads may not assign Q or Z at all, or assign it to various other numbers, 1 for Australian Classic, 0 for UK Classic and Mobile 1.&lt;p&gt;&lt;a href=&quot;http://www.dialabc.com/motion/keypads.html&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;www.dialabc.com&amp;#x2F;motion&amp;#x2F;keypads.html&lt;/a&gt;&lt;p&gt;Similarly, special characters can be entered via numerous mechanisms on phone keyboards.&lt;p&gt;My suspicion is that there&amp;#x27;s a contractual requirement somewhere to retain compatibility with an existing infrastructure somewhere.</text></item></parent_chain></comment><story><title>Passwords for JetBlue accounts cannot contain a Q or a Z</title><url>http://help.jetblue.com/SRVS/CGI-BIN/webisapi.dll?New,Kb=askBlue,case=obj(403864)</url></story>